sensor MITSUBISHI DIAMANTE 1900 Owner's Guide

3-34 ENGINEANDENGINEOVERHAUL
9. Remove the front cover mounting bolts. Note
the lengths of the mounting bolts as they are re-
moved for proper installation.
10. Remove the front case assembly and oil
pump assembly.
11. Remove the oil pump cover.
12. Remove the inner and outer gears from the
front case.
To install 13. Remove all gasket material from the mating
surfaces and clean all parts.
14. Thoroughly coat both oil pump gears with
clean engine oil and install them in the correct direc-
tion of rotation.
15. Install the pump cover and tighten the bolts to
84 inch Ibs. (10 Nm).
16. Coat the relief valve and spring with clean en-
gine oil. Install them and tighten the plug to 33 ft.
Ibs. (45 Nm).
17. Install a new front crankshaft seal and coat
the lips of the seal with clean engine oil.
18. Install the front case and oil pump assembly
to the engine block using a new gasket. Tighten the
bolts to loft. Ibs. (14 Nm)
19. Install the oil screen with new gasket. Torque
the screen bolts to 14 ft. Ibs. (19 Nm).
20. Install the oil pan.
21. Install the crankshaft sprocket and timing
belt. Refer to the timing belt procedure in this sec-
tion.
22. Fill the crankcase to the proper level.
Operating the engine without the proper
amount and type of engine oil will result in
severe enoine damaae.
23. Connect the negative battery cable.
1.6L, 2.OL and 2.4L Engines
p See Figures 146, 147, 148, and 149
*Whenever the oil pump is disassembled or
the cover removed, the gear cavity must be
filled with petroleum jelly to seal the pump
and act as a prime. Do not use grease.
1. Disconnect the negative battery cable.
2. Rotate the engine so No. 1 cylinder is on Top
Dead Center (TDC) of its compression stroke.
3. Drain the engine oil.
The EPA warns that prolonged contact with
used engine oil may cause a number of skin
disorders, including cancer! You should
make every effort to minimize your exposure
to used engine oil. Protective gloves should
be worn when changing the oil. Wash your
hands and any other exposed skin areas as
soon as possible afler exposure to used en-
gine oil. Soap and water, or waterless hand
cleaner should be used.
4 Using the proper equipment, support the
weight of the engine Remove the front engine mount
bracket and accessory drive belts.
5 Remove timing belt upper and lower covers.
6. Remove the timing belt and crankshaft
sprocket. Refer to the timing belt procedure in this
section. 7. Detach the electrical connector from the oil
pressure sending unit and remove the oil pressure
sensor. Remove the oil filter and the oil filter bracket.
8. Remove the oil pan, oil screen and gasket.
9. Using special tool MD998162, remove the
plug cap in the engine front cover.
10. Remove the plug on the side of the engine
block. Insert a Phrllips screwdriver with a shank di-
ameter of 0.32 in. (8mm) into the plug hole. This will
hold the silent shaft.
11. Remove the driven gear bolt that secures the
oil pump driven gear to the silent shaft.
12. Remove the front cover mounting bolts. Note
the lengths of the mounting bolts as they are re-
moved for proper installation.
13. Remove the front case cover and oil pump
assembly. If necessary, the silent shaft can come out
with the cover assembly.
14. Remove the oil pump cover, located on the
back of the engine front cover. Remove the oil pump
drive and driven gears.
15. After disassembling the oil pump, clean all
components and remove gasket material from mating
surfaces.
16. Assemble the oil pump gears into the front
case and rotate it to ensure smooth rotation and no
looseness. Be sure there is no ridge wear on the con-
tact surface between the front case and the gear sur-
face of the oil pump front cover.
To install 17. Align the timing mark on the oil pump drive
gear with that on the driven gear and install them into
the engine front case. Apply engine 011 to the gears.
18. Install the oil pump cover and tighten the re-
tainer bolts to 13 ft. Ibs. (18 Nm).
19. Using the appropriate driver, install a new
crankshaft seal into the front case.
Phrllips screwdrrver
7923PG71 Fig. 146 Holding the silent shaft for oil
pump gear removal-2.01 engine
7923PG73 Fig. 148 Aligning oil pump timing marks-
2.OL ermine
20. Position new front case gasket in place. Set
seal guide tool MD998285 on the front end of the
crankshaft to protect the seal from damage. Apply a
thin coat of oil to the outer circumference of the seal
pilot tool.
21. Install the front case assembly through a new
front case gasket and temporarily tighten the flange
bolts.
22. Mount the oil filter on the bracket with new oil
filter bracket gasket in place. Install the bolts with
washers and tighten to 14 ft. Ibs. (19 Nm).
23. Insert a Phillips screwdriver into the hole in
the left side of the engine block to lock the silent
shaft in place.
24. Install the oil pump drive gear onto the left
silent shaft. Tighten the driven gear bolt to 27 ft. Ibs.
(37 Nm).
25. Install a new O-ring to the groove in the front
case and install the plug cap. Using the special tool
MD998162, tighten the cap to 17 ft. Ibs. (24 Nm).
26. Install the oil screen in position with new
gasket in place.
27. Clean both mating surfaces of the oil pan and
the cylinder block. Apply sealant In the groove in the
oil pan flange.
*After applying sealant to the oil pan, do
not exceed 15 minutes before installing the
oil pan.
28. Install the oil pan to the engine and secure
with the retainers. Tighten bolts to 5 ft. Ibs. (7 Nm).
29. install the oil pressure gauge unit and the oil
pressure switch. Connect the electrical harness con-
nector.
30. Install the oil cooler. Secure with oil cooler
bolt tightened to 31 ft. Ibs (43 Nm).
31. Refill the crankcase.
32. Install new oil filter.
7923PG72 Fig. 147 Use the special socket and holder
:o remove the balance shaft plug-2.0 en-
7ine
L= Bolt length below
head /mm (cn.)]
Fig. 149 Front case bolt identification-
?.OL and 2.4L engines

ENGlNEANDENGlNEOVERHiUL 3-45
TIMINQ MARKS ON RIQHT SIDE VALVE COVER TIMING MARKS ON LEFT SIDE VALVE COVER
CRANKSHAFT SPROCKETS
91251gb5 :ig. 185 Crankshaft and camshaft sprocket alignment for proper timing belt replacement-1992-94 Mitsubishi 3.OL DOHC engine
4. Remove the cruise control actuator.
5. Remove the alternator. Remove the air hose
and pipe.
6. Remove the belt tensioner assembly and the
power steering belt.
7. Remove the crankshaft pulley.
8. Disconnect the brake fluid level sensor.
9. Remove the timing belt upper cover.
10. Using the proper equipment, slightly raise the
engine to take the weight off the side engine mount.
Remove the engine mount bracket.
11. Remove the alternator/air conditioner idler
pulley.
12. Remove the engine support bracket. The
mounting bolts are different lengths; mark them for
proper installation.
13. Remove the timing belt lower cover. Timing
bolt cover mounting bolts are different in length, note
their position during removal.
14. If the same timing belt will be reused, mark
the direction of the timing belt’s rotation for installa-
tion in the same dlrection. Make sure the engine is
positioned so the No. 1 cylinder is at the TDC of its
compression stroke and the sprockets’timing marks
are aligned with the engine’s timing mark indicators
on the valve covers or head.
15. Loosen the timing belt tensioner bolt and re-
move the belt.
16. Remove the tensioner assembly.
To install:
17. If the auto tensioner rod is fully extended, re-
set it as follows:
a. Clamp the tensioner in a soft-jaw vice in
level position.
b. Slowly push the rod in with the vice until
the set hole in the rod is aligned with the hole in
the cylinder. c. Insert a stiff wire into the set holes to retain
the position.
d. Remove the assembly from the vice.
18. Leave the retaining wire in the tension and in-
stall to the engine.
19. If the timing marks of the camshaft sprockets
and crankshaft sprocket are not aligned at this point,
proceed as follows:
*Keep fingers out from between the
camshaft sprockets. The sprockets may move
unexpectedly because of valve spring pres-
sure and could pinch fingers.
a. Align the mark on the crankshaft sprocket
with the mark on the front case. Then move the
sprocket 2 teeth clockwise to lower the piston so
the valve can’t touch the piston when the
camshafts are being moved.
b. Turn each camshaft sprocket 1 at a time to
align the timing marks with the mark on the valve
cover or head. If the intake and exhaust valves of
the same cylinder are opened simultaneously,
they could interfere with each other. Therefore, if
any resistance is felt, turn the other camshaft to
move the valve.
c. Align the timing mark of the crankshaft
sprocket, then continue 1 tooth farther in the
counterclockwise direction to facilitate belt instal-
lation.
20. Using 4 spring loaded paper clips to hold the
belt on the cam sprockets, install the belt to the
sprockets in the following order:
l M-exhaust camshaft sprocket for the
front head
l 2nd-intake camshaft sprocket for the
front head
l trd-water pump pulley
l 5th-exhaust camshaft sprocket for tile
rear head
l Ah-intake camshaft sprocket for the rear
l Gth-idler pulley head l 7th-crankshaft sprocket l 8th-tensioner pulley
21. Turn the tensioner pulley so its pin holes are
located above the center bolt. Then press the ten-
sioner pulley against the timing belt and simultane-
ously tighten the center bolt.
22. Make certain that all timing marks are still
aligned. If so, remove the 4 clips.
23. Turn the crankshaft l/d turn counterclockwise,
then turn it clockwise until all timing marks are
aligned.
24. Loosen the center bolt on the tensioner pul-
ley. Using tool MD998767 or equivalent and a torque
wrench, apply a torque of 7 ft. Ibs. (10 Nm). Tighten
the tensioner bolt; make sure the tensioner doesn’t
rotate with the bolt.
25. Remove the set wire attached to the auto ten-
sioner, if the wire was not previously removed.
26. Rotate the crankshaft 2 complete turns clock-
wise and let it sit for approximately 5 minutes. Then,
make sure the set pin can easily be inserted and re-
moved from the hole in the tensioner.
27. Measure the auto tensioner protrusion (the
distance between the tensioner arm and auto ten-
sioner body) to ensure that it is within 0.15-0.18 in.
(3.8-4 5mm). If out of specification, repeat Steps
l-4 until the specified value is obtained.
28. Make sure all pieces of packing are posi-
tioned in the inner grooves of the lower cover, posi-
tion cover on engine and install mounting bolts in
their original location.

3-46 ENGINEANDENGINEOVERHAUL
29. Install the engine support bracket and secure
using mounting bolts in their original location. Lubri-
cate the reaming area of the reamer bolt and tighten
slowly.
30. Install the idler pulley.
31. Install the engine mount bracket. Remove the
engine support fixture.
32. Make sure all pieces of packing are posi-
tioned in the inner grooves of the upper cover and in-
stall.
33. Connect the brake fluid level sensor.
34. Install the crankshaft pulley. Tighten the bolt
to 130-137ft. Ibs. (180-190 Nm).
35. install the belt tensioner assembly and the
power steering belt.
36 install the air hose and pipe.
37 Install the alternator.
38. Install the cruise control actuator.
39. Install the engine undercover.
40. Connect the negative battery cable.
199546 MODELS
# See Figure 186
1, Position the engine so the No. 1 cylinder is at
TDC of its compression stroke.
2. Disconnect the negative battery cable.
3. Remove the engine undercover.
4 Remove the cruise control actuator. 5. Remove the alternator, Remove the air hose the engine’s timing mark indicators on the rear timing
and pipe.
6. Remove the belt tensioner assembly and the
power steering belt.
7. Remove the crankshaft pulley.
8. Disconnect the brake fluid level sensor.
9. Remove the timing belt upper cover.
10. Using the proper equipment, slightly raise the
engine to take the weight off the side engine mount.
Remove the engine mount bracket.
11, Remove the alternator/air conditioner idler
..,,ll^,. covers.
Turning the camshaft sprocket when the tim-
ing belt is removed could cause the valves to
contact with the pistons, resulting in severe
engine damage.
15. Remove the bolts that secure the auto-ten-
sioner to the engine block and remove the tensioner.
pu,ey. 12. Remove the engine support bracket. The To install:
mounting bolts are different lengths; mark them for
orooer installation. *The auto-tensioner assembly must be re-
set to correctlv adiust belt tension. , . 13. Remove the timing belt lower cover. Timing
bolt cover mounting bolts are different in length, note
their position during removal.
Be sure to disconnect the negative battery
cable. Wait at least 90 seconds after the neg-
ative battery cable is disconnected to prevent
possible deployment of the air bag.
14. If the same timing belt WIII be reused, mark
the direction of the trming belts rotation for installa-
tion In the same direction, Be sure the engine is posi-
tioned so the No. 1 cylinder is at the TDC of its com-
pression stroke and the timing marks are aligned with _ -
16. Loosen the center bolt of tensioner pulley to
provide timing belt slack.
17. Remove the timing belt assembly.
18. Posrtion the auto-tensioner into a vise with
soft iaws. The olua at the rear of tensioner protrudes,
be sure to usea v&her as a spacer to protect the
plug from contacting vise jaws.
19. Slowly push the rod mto the tensioner until
the set hole in rod is aligned with set hole in the
auto-tensioner.
20. Insert a 0.055 in. (1.4mm) wire into the
aligned set holes, Remove the tensioner from the vise
and install it on the engine.
21. Tighten tensioner mounting bolts to 17 ft. Ibs.
(24 Nm).
Timing marks
(on right
rocker cover)
Camshaft sprocket
Timing marks
mark (on oil pump case)
Crankshaft sprocket
Fig. 186 Sprocket alignment for timing belt installation-1995116 Diamante with the 3.N (6672) DDDD engine

ENGINEANDENGINEOVERHAUL 3-47
DO NOT rotate or turn the camshafts when re-
moving the sprockets or severe engine dam-
age will result from internal component in-
terference.
22. Align the mark on the crankshaft sprocket
with the mark on the front case. Then, move the
crankshaft sprocket 1 tooth counterclockwise.
23. Align the timing marks of the camshafts with
the marks on the rear covers.
24. Using large paper clips to secure the timing
belt to the sprockets, install the timing belt in the fol-
lowing order. Be sure camshafts-to-cylinder heads
and crankshaft-to-front cover timing marks are
aligned. Install the timing belt around the pulleys in
the following order:
a. Exhaust camshaft sprocket (front bank).
b. Intake camshaft sprocket (front bank).
c. Water pump pulley.
d. Intake camshaft sprocket (rear bank).
e. Exhaust camshaft sprocket (rear bank).
f. Tensioner pulley.
g. Crankshaft pulley.
h. Idler pulley.
*Since the camshaft sprockets turn easily,
secure them with box wrenches when in-
stalling the timing belt.
25. Align all timing marks on the crankshaft and
raise the tensioner pulley against the belt to remove
slack, snug tensioner bolt.
26. Check the alignment of all the timing marks
and remove the clips that secure the timing belt to the
camshaft sprockets.
27. Rotate the engine 1/4 turn counterclockwise,
then rotate the engine clockwise to align the timing
marks. Check that all the timing marks are in align-
ment.
28. Loosen the center bolt on the tensioner pul-
ley.
29. Using tool MD998752 or equivalent and a
torque wrench, apply 84 inch Ibs. (10 Nm) to the tool
on the tensioner. Tighten the tensioner bolt to 35 ft.
Ibs. (49 Nm) and be sure the tensioner does not ro-
tate with the bolt. 30. Rotate the crankshaft two complete turns
clockwise and let it sit for approximately five minutes.
Then, check that the set pin can easily be inserted
and removed from the hole in the auto-tensioner.
31. Remove the set wire attached to the auto-ten-
sioner
32. Measure the auto-tensioner protrusion (the
distance between the tensioner arm and auto-ten-
sioner body) to ensure that it is within 0.15-0.18 in.
(3.8-4.5mm). If out of specification, repeat adjust-
ment procedure until the specified value is obtained.
33. Check again that the timing marks on all
sprockets are in proper alignment.
34. Install the timing belt covers and all other ap-
plicable components.
3.51 Engine
p See Figure 187
1. Disconnect the negative battery cable.
2. Drain the cooling system.
Never open, service or drain the radiator or
cooling system when hot; serious burns can
occur from the steam and hot coolant. Also,
when draining engine coolant, keep in mind
that cats and dogs are attracted to ethylene
giycoi antifreeze and could drink any that is
left in an uncovered container or in puddles
on the ground. This will prove fatal in suffi-
cient quantities. Always drain coolant into a
sealable container. Coolant should be reused
unless it is contaminated or is several years
old.
3. Remove the drive belts.
4. Remove the upper radiator shroud.
5. Remove the fan and fan pulley.
6. Without disconnecting the lines, remove the
power steering pump from its bracket and position it
to the side Remove the pump brackets.
7. Remove the belt tensioner pulley bracket.
8. Without releasing the refrigerant, remove the
air conditioning compressor from its bracket and po-
sition it to the side.
9. Remove the bracket.
Timing marks
liming marks
Tinning marks
79245934 Fig. 187 Clean the timing marks to verify their position when aligning-3.51 engine
10. Remove the cooling fan bracket.
11, On some vehicles It may be necessary to re-
move the pulley from the crankshaft to access the
lower cover bolts.
12. Remove the timing belt cover bolts and the
upper and lower covers from the engme.
13. Detach the crankshaft position sensor con-
nector
14. Using SST MB9g67-01 and MD998754, or
their equivalents, remove the crankshaft pulley from
the crankshaft.
15. Use a shop rag to clean the timing marks to
assist in properly aligning the timing marks.
16. Loosen the center bolt on the tension pulley
and remove the timing belt.
@if the same timing belt will be reused,
mark the direction of timing belt’s rotation,
for installation in the same direction. Be sure
engine is positioned so No. 1 cylinder is at
the TDC of it’s compression stroke and the
sprockets timing marks are aligned with the
engine’s timing mark indicators.
17. Remove the auto-tensioner, the tension pul-
ley and the tension arm assembly.
18. Remove the sprockets by holding the hexago-
nal portion of the camshaft with a wrench while re-
moving the sprocket bolt.
To install: 19. Install the crankshaft pulley and turn the
crankshaft sprocket timing mark forward (clockwise)
three teeth to move the piston slightly past No. 1
cylinder top dead center.
20. If removed, install the camshaft sprockets and
tighten the bolts to 64 ft. Ibs. (88 Nm).
21, Align the timing mark of the left bank side
camshaft sprocket.
22. Align the timing mark of the right bank side
camshaft sprocket, and hold the sprocket with a
wrench so that it doesn’t turn.
23. Set the timing belt onto the water pump pul-
ley.
24. Check that the camshaft sprocket timing mark
of the left bank side is aligned and clamp the timing
belt with double clips.
25. Set the timing belt onto the idler pulley.
if any binding is felt when adjusting the tim-
ing belt tension by turning the crankshaft,
STOP turning the engine, because the pis-
tons may be hitting the valves.
26. Turn the crankshaft one turn counterclock-
wise and set the timing belt onto the crankshaft
sprocket.
27. Set the timing belt on the tension pulley.
28. Place the tension pulley pin hole so that it is
towards the top. Press the tension pulley onto the
timing belt, and then provisionally tighten the fixing
bolt. Tighten the bolt to 35 ft. Ibs. (48 Nm).
29. Slowly turn the crankshaft two full turns in the
clockwise direction until the timing marks align. Re-
move the four double clips.
30. Install the crankshaft position sensor connec-
tor.
31. Install the upper and lower covers on the en-
gine and secure them with the retaining screws. Be
sure the packing is properly positioned in the inner
grooves of the covers when installing.

ENGINEANDENGINEOVERHAUL 3-49
011 pump
MS8
7923PG51 Fig. 196 Crankshaft seal installation-Dia
mante shown, others similar
:ig. 197 Camshaft, rocker arm and shaft as
remblies-1.5L engine
7923PG5 Fig. 198 Positioning of the camshaft dowe
pin-Mirage 1.5L (4615) engine
10. Remove the camshaft sprocket from the
camshaft. Note the positioning of the dowel pin at the
end of the camshaft.
11. Remove the camshaft oil seal from the front
of the cylinder head.
12. Remove the camshaft from the head.
13. Carefully check all parts for damage and
wear
To install:
14. Lubricate the camshaft with heavy engine oil
and slide it mto the head. Be sure to position the
dowel pin at the 12 o’clock position.
15. Check the camshaft end-play between the
thrust case and camshaft. The camshaft end-play
should be 0.002-0.008 m (0.05-O 20mm). If the
end-play is not within specification, replace the
camshaft thrust bearing.
16 Install a new camshaft oil seal. Be sure to Iu-
bricate the lips of the seal with clean engine 011.
17. Install the camshaft sprocket and install the
mountrng bolt. Tighten the bolt to 51 ft. Ibs. (70 Nm)
while holding the camshaft from turning.
18. Install the timing belt assembly.
19. Install the timing belt covers.
20. Install the rocker shaft assemblies. Torque the
bolts gradually and evenly to 23 ft. Ibs. (32 Nm).
21. Check valve adjustment and install the valve
cover with a new gasket. Tighten the valve cover bolt
to 16 inch Ibs (1.8 Nm).
22 Align the distributor marks and install the
distributor.
23. Connect the accelerator cable, breather hose
and PCV hose.
24. Connect the negative battery cable and check
the ignition timing
1.8L Engine
# See Figure 199
1. Disconnect the negative battery cable
2. Rotate the engine and position the No. 1 pis-
ton to TDC of its compression stroke.
3. Label and disconnect the spark plug cables.
4. Matchmark the positronrng of the distributor
housing and the positioning of the distributor rotor to
the engine block and remove the distributor.
5. Detach the air flow sensor connector and re-
move the air cleaner case cover.
6. Drsconnect the accelerator cable, breather
hose and PCV hose connections.
7. Remove the rocker cover and discard the
gasket.
8. Loosen both rocker arm shaft assemblies
gradually and evenly and remove the rocket shafts
from the vehicle. Do not disassembly rocker arms
and rocker arm shaft assemblies.
9. Remove the timing belt covers.
DO NOT allow the camshaft or the crankshaft
to rotate after the timing belt is removed!
10. Remove the timing belt assembly.
11. Holding the camshaft sprocket from turning,
loosen and remove the bolt that secures the sprocket.
12. Remove the camshaft sprocket from the
camshaft. Note the positioning of the dowel pin at the
end of the camshaft.
13. Remove the camshaft oil seal from the front
of the cylinder head.
14. Remove the camshaft from the head.
(r.mblies-1.8L Agine g3i53033 Fig 199 Camshaft rocker arm and shaft as-
15. Carefully check all parts for damage and
wear.
To install:
16. Lubricate the camshaft journals and camshaft
with clean engine oil and install the camshaft in the
cylinder head. Be sure to position the dowel pin at
the end of the camshaft as noted during the removal
procedure.
17. Check the camshaft end-play between the
thrust case and camshaft The camshaft end-play
should be 0.002-0.008 in. (0.05-0.20mm). If the
end-play
IS not within specification, replace the
camshaft thrust bearing
18. Install a new camshaft oil seal. Be sure to Iu-
bricate the lips of the seal with clean engine oil.
19. Install camshaft sprocket and torque the re-
tainer bolt to 65 ft. Ibs. (90 Nm). Be sure to secure
the sprocket while tightening the bolt.
20 Install the timing belt assembly.
21. Install the timing belt covers.
22. Install the rocker arm and shaft assemblies.
Tighten the rocker arm shaft retainer bolts to 23 ft.
Ibs (32 Nm).
23 Check the valve adjustment and install the
valve cover with a new gasket. Tighten the valve
cover bolts to 29 inch Ibs. (3.3 Nm).
24. Align the distributor marks and install the
distributor.
25. Connect the spark plug cables.
26. Connect the accelerator cable, breather hose
and PCV hose.
27. Attach the air flow sensor connector and in-
stall the air cleaner case cover.
28. Connect the negative battery cable.
29. Run the engine at idle until normal operating
temperature is reached.
30. Check idle speed and ignition timing and ad-
just as required.
2.OL SDHC Engine
# See Figure 200
1. Disconnect the negative battery cable.
2. Disconnect the breather and the PCV hoses

ENGlNEANDENGlNEOVERHALiL 3-51
:ig. 203 Camshaft, rocker arm and shaft assemblies-2.41 engine 9315393'
Intake side Exhaust side
7923PG57 Fig. 204 Camshaft identification-2.41 en-
gine
9. Remove the intake and exhaust camshafts.
10. Remove the rocker arms and lash adjusters
*It is essential that all parts be kept in the
same order and orientation for reinstallation.
In order to prevent confusion during installa-
tion, be sure to mark and separate all parts.
To install:
11. Install the lash adjusters and rocker arms into
the cylinder head. Lubricate lightly with clean oil
prior to installation.
12. Lubricate the camshafts with heavy engine oil
and position the camshafts on the cylinder head.
13 Check the camshaft journals and lobes for
wear or damage. Also, check the cylinder head oil
holes for clogging. Visually inspect the rocker arm
roller and replace if dented, damaged or evidence of
seizure is evident. Check the roller for smooth rota-
tion. Replace If excess play or binding is present.
Also, inspect the valve contact surface for possible
damage or seizure. It is recommended that all rocker
arms and lash adjusters be replaced together.
*Do not confuse the intake camshaft with
the exhaust camshaft. The intake camshaft
has a split on the rear face for driving the ,
crank angle sensor.
14. Make sure the dowel pin on both camshaft
sprocket ends are located on the top.
15. Install the bearing caps. Tighten the caps in
sequence and rn 2 or 3 steps. No 2 and 5 caps are of
the same shape. Check the markings on the caps to
identify the cap number and intake/exhaust symbol. Only 1 (intake) or I? (exhaust) is stamped on No. 1
bearing cap Also, make sure the rocker arm is cor-
rectly mounted on the lash adjuster and the valve
stem end. Torque the retaining bolts to 15 ft. Ibs. (20
Nm).
16. Apply a coating of engine oil to the oil seal.
Using the proper size driver, press-fit the seal into
the cylinder head.
17. Install the camshaft sprockets. While holding
the camshaft at its hexagon, between number 2 and 3
journals tighten sprocket bolts to 58-72 ft. Ibs.
(80-l 00 Nm).
18. Install the timing belt, covers and related
components.
19. Install the valve cover, using new gasket, and
reconnect all related components
20. Reconnect the negative battery cable.
3.OL DOHC Engine
# See Figures 205 and 206
1. Relieve the fuel system pressure.
2. Disconnect negative battery cable.
3. Remove the intake manifold plenum.
4. Remove the timing belt cover and the timing
belt.
DO NOT rotate the crankshaft or camshafts
after the timing belt has been removed. If ro-
tated, severe internal engine damage will re-
sult from the pistons hitting the valves.
5. Remove the center cover, breather, PCV
hoses, and the spark plug cables.
6. Remove the rocker cover and the semi-circu-
lar packing.
7. Matchmark the position of the crankshaft po-
sition sensor at the rear of the camshaft, then remove
the sensor.
8. If equipped with a camshaft sensor, remove
the sensor from the front of the engine.
9 Being sure to hold the flats of the camshaft,
loosen the camshaft sprocket bolts.
10. Noting the positionmg and location of the
sprockets, remove the sprockets from the camshafts.
*Be sure to note the positioning of the knock
pin at the end of the camshafts for reinstalla-
tion purposes.
*Be sure to keep the valve train components
labeled and in proper order for reassembly.
11. Loosen the bearing cap bolts in 2-3 steps.
12. Label and remove all camshaft bearing caps.
*If the bearing caps are difficult to remove,
use a plastic hammer to gently tap the com-
ponents.
13. Mark the components and remove the intake
and the exhaust camshafts.
14. Remove the rocker arms and the lash ad-
justers. Be sure to note the location of the valve train
components for reinstallation purposes.
1 semblies-3.01 DOHC engine
I
Left bank
7923PG58 Fig. 206 Proper positioning of the camshaft knock pins-3.01 DOHC engine

.
3-52 ENGINEANDENGINEOVERHAUL
15. Check the camshaft journals for wear or dam-
age. Check the cam lobes for damage. Also, check
the cylinder head oil holes for clogging.
To install:
*Lubricate the valve train components with
clean engine oil.
16. Bleed and install the lash adjusters to the to
the original bores in the cylinder head.
17. Install the rocker arms to the cylinder head.
18. Lubricate the camshafts with clean engine oil
and position the camshafts on the cylinder head
Be sure to properly position the knock pins of
the camshaft to prevent valve to piston inter-
ference.
*Do not confuse the intake camshaft with
the exhaust camshaft. The intake camshaft
on the Diamante has a B or J stamped on the
hexagon depending on the application. The
exhaust camshaft on the Diamante has a D or
K stamped on the hexagon depending on ap-
plication.
-Install the bearing caps according to the
identification mark and cap number. Bearing
caps No. 2,3 and are marked as such. The
caps also are marked I for intake or E for ex-
haust.
19 Install the bearing caps. Tighten the caps in
sequence, gradually in 2 or 3 steps Caps 2,3 and 4
have a front mark. Install with the mark aligned with
the front mark on the cylinder head. Torque the re-
taining bolts for caps No. 2,3 and 4 to 8 ft. Ibs. (11
Nm) and torque the retaining bolts for the front and
rear caps to 14 ft. Ibs. (20 Nm).
20. Apply a coating of engine oil to the oil seals
and install the oil seals to the front and rear of the
camshafts.
21. Holding the flats of the camshaft, install and
tighten the sprocket bolts to 65 ft. Ibs. (90 Nm).
22. If removed, install the camshaft position sen-
sor and tighten the mounting bolts to 78 inch Ibs. (9
Nm).
23. Aligning the matchmark, install the crankshaft
position sensor at the rear of the camshaft and
tighten the mountrng nut to 7 ft. Ibs. (12 Nm).
24. Align the marks on the camshaft and crank-
shaft sprockets. Install the timing belt assembly.
25. Install the rocker cover and the semi-circular
packing.
26. Install the intake manifold plenum.
27. Install the spark plug cables, center cover,
breather and PCV hoses.
28. Connect the negative battery cable and check
for leaks.
3.OL SDHC Engine
ti See Figures 207, 208, 209, and 210
1. Disconnect the negative battery cable,
2. Rotate and position the engine to TDC of
compression stroke.
3. If removing the right side (front) camshaft,
matchmark the distributor rotor and distributor hous-
ing to the engine block and remove the distributor.
4. Remove the Intake manifold plenum stay
bracket. Fig. 207 Camshaft, rocker arm and shaft as-
iemblies-3.01 SDHC engine
Siit 7923'659 Fig. 208 Right bank camshafl identifica-
tion-3.01 SDHC engine
Right bank
Left bank
7923PG60 Fig. 209 Proper positioning of the
:amshafts-3.OL SDHC enoine

Tmng bolt side Armwmark(cql~ndertmad)
7923PG61
:ig. 210 Alignment of the rocker shafts and application of sealant-3.01 SDHC engine
5. Remove the distributor housing adapter and
,. ,.^.
bearmg caps, as an assembly 11. Remove the rocker arms, rocker shafts and
aiscara tne u-rmg.
^ -
6; Kemove the valve covers and the tlmmg belt.
7 Using camshaft sprocket holding tool
MB9g67 and MD998719 or equivalent, hold the
sprocket and loosen the bolt.
8. Remove the bolt and note the positioning of
the of the knock pin at the end of the camshaft and
remove the sprocket.
9. Install auto lash adjuster retainer tools
MD998443 or equivalent, on the rocker arms.
*Be sure to note the position of the rocker
arms, rocker shafts and bearing caps for re-
installation purposes.
10 Remove the camshaft bearing caps but do not
remove the bolts from the caps. 12. Remove the camshaft from the cylinder head.
13. Inspect the bearing journals on the camshaft,
cylinder head, and bearing caps.
To install:
*The right bank camshaft is identified by a
4mm slit at the rear end of the camshaft.
14. Lubricate the camshaft journals and camshaft
with clean engme oil and install the camshaft in the
cylinder head Be sure to properly position the knock
pin of the camshaft as noted during removal.
15. Apply sealer at the ends of the bearing caps
and install the rocker arms, rocker shafts and bearing
caps as an assembly Properly positron the arrows on
the bearing caps.

EMISSION CONTROLS 4-2
CRANKCASEVENTILATIONSYSTEM 4-2
OPERATION 4-2
COMPONENTTESTING 4-2
REMOVAL &INSTALLATION 4-2
EVAPORATIVEEMISSIONCONTROLS 4-2
OPERATION 4-2
COMPONENTTESTING 4-3
REMOVAL&INSTALLATION 4-4
EXHAUSTGASRECIRCULATION
SYSTEM 4-5
OPERATION 4-5
COMPONENTTESTING 4-5
REMOVAL&INSTALLATION 4-6
ELECTRONIC ENGINE CONTROLS 4-7
ENGlNECONTROLUNIT/POWERTRAIN
CONTROLMODULE(ECU/PCM) 4-7
OPERATION 4-7
REMOVAL&INSTALLATION 4-7
OXYGENSENSOR 4-8
OPERATION 4-8
TESTING 4-8
REMOVAL&INSTALLATION 4-8
IDLEAIRCONTROLMOTOR 4-9
OPERATION 4-9
TESTING 4-9
REMOVAL&INSTALLATION 4-9
ENGINECOOLANTTEMPERATURE
SENSOR 4-10
OPERATION 4-10
TESTING 4-10
REMOVAL&INSTALLATION 4-10
INTAKEAIRTEMPERATURESENSOR 4-10
OPERATION 4-10
TESTING 4-11
REMOVAL&INSTALLATION 4-11
MASSAIRFLOWSENSOR 4-11
OPERATION 4-11
TESTING 4-11
REMOVAL&INSTALLATION 4-11
MANIFOLDABSOLUTEPRESSURE
SENSOR 4-12
OPERATION 4-12
TESTING 4-12
REMOVAL&INSTALLATION 4-13
THROTTLEPOSITIONSENSOR 4-13
OPERATION 4-13
TESTING 4-13
REMOVAL&INSTALLATION 4-13
CAMSHAFT POSITIONSENSOR 4-14
OPERATION 4-14
TESTING 4-14
REMOVAL&INSTALLATION 4-14
CRANKSHAFTPOSlTlONSENSOR/CRANK
ANGLE SENSOR 4-14
OPERATION 4-14 I
TESTING 4-15 REMOVAL&INSTALLATION 4-15
COMPONENT LOCATIONS 4-16
OBD-1 TROUBLE CODES 4-26
GENERALINFORMATION 4-26
CHECKENGINVMALFUNCTION
INDICATOR LIGHT 4-26
SERVICEPRECAUTIONS 4-26
READING CODES 4-26
WITHASCANTOOL 4-26
WITHOUTASCANTOOL 4-27
CLEARINGCODES 4-27
DIAGNOSTICTROUBLECODES 4-27
OBD-II TROUBLE CODES 4-27
GENERALINFORMATION 4-27
READING CODES 4-27
WITHASCANTOOL 4-27
WITHOUTASCANTOOL 4-27
CLEARINGCODES 4-28
WITHASCANTOOL 4-28
WITHOUTASCANTOOL 4-28
DIAGNOSTICTROUBLECODES 4-28
FLASH OUTCODELIST 4-32
VACUUM DIAGRAMS 4-36

4-2 DRIVEABILITYAND EMISSIONS CONTROLS
OPERATION
p See Figures 1, 2, and 3
All engines are equipped with the Positive
Crankcase Venhlation (PCV) system. The PCV sys-
tem vents crankcase gases into the engine air intake
where they are burned with the fuel and air mrxture.
The PCV system keeps pollutants from being re-
leased into the atmosphere It also helps to keep the
engine 011 clean, by ridding the crankcase of moisture
and corrosive fumes. The PCV system consists of the
PCV valve, the nipple in the air intake and the con-
necting hoses.
Incorrect operation of the PCV system can cause
multiple driveability symptoms.
A plugged valve or hose may cause’
l Rough Idle l Stalling or slow idle speed l Oil leaks
tT9574goi Fig. 1 Typical PCV system airflow
89574g0r5 Fig. 3 . . .
or mounted in a grommet on the
valve cover
l Sludge in en ine
A leakrng valve or ose would cause: i?
l Rough idle l Stalling l High idle speed
p See Figures 4 and 5
1. Disconnect the ventilation hose from the PCV
valve. Remove the PCV valve from the engine Once
removed, reconnect the ventilation hose to the valve.
2. Start the engine and allow to idle. Place a fin-
ger over open end of the PCV valve. Make sure intake
manifold vacuum is felt on finger.
3. If vacuum is not felt, the PCV valve may be re-
stricted.
4. Turn the engine
OFF and remove the PCV
valve from the hose.
5. Insert a thin stick into the threaded end of the
PCV valve. Push on the inner plunger and inspect for
movement.
6. If plunger inside the PCV valve is not free to
move back and forth, the valve is clogged and WIII re-
quire replacement.
*It is possible to clean the valve using the
appropriate solvent, but replacement is rec-
ommended.
REMOVAL&INSTALLATION
For PCV valve removal and installation, please re-
fer to Section 1 of this manual.
89574QO’ Fig. 4 With the engine idling, check the end
of the PCV valve to see if vacuum is present
Positive crankcase
ventilation
89574go6 Fig. 5 Inspect the PCV valve for inner
plunger movement. If the plunger is bound
or sticking, replace the valve OPERATION
p See Figures 6 and 7
Changes in atmospheric temperature cause fuel
tanks to breathe, that is, the air within the tank ex-
pands and contracts with outside temperature
changes. If an unsealed system was used, when the
temperature rises, air would escape through the tank
vent tube or the vent in the tank cap. The air which
escapes contains gasoline vapors.
The Evaporative Emission Control System pro-
vides a sealed fuel system with the capability to store
and condense fuel vapors. When the fuel evaporates
in the fuel tank, the vapor passes through the EVAP
emission valve, through vent hoses or tubes to a car-
bon filled evaporative canister. When the engine is
operahng the vapors are drawn into the intake mani-
fold and burned during combustion.
A sealed, maintenance free evaporative canister is
used The canister is filled wrth granules of an acti-
vated carbon mixture. Fuel vapors entering the canis-
ter are absorbed by the charcoal granules. A vent cap
is located on the top of the canister to provide fresh
air to the canister when it is being purged. The vent
cap opens to provide fresh air into the canister, which
circulates through the charcoal, releasing trapped va-
pors and carrying them to the engine to be burned.
Fuel tank pressure vents fuel vapors into the can-
ister. They are held in the canister until they can be
drawn into the intake manifold. The canister purge
valve allows the canister to be purged at a pre-deter-
mined time and engine operating conditions.
Vacuum to the canister is controlled by the canis-
ter purge valve. The valve IS operated by the PCM.
The PCM regulates the valve by switching the ground
circuit on and off based on engine operating condi-
tions When energized, the valve prevents vacuum
from reaching the canister. When not energized the
valve allows vacuum to purge the vapors from the
canister.
During warm up and for a specified time after hot
starts, the PCM energizes (grounds) the valve pre-
venting vacuum from reaching the canrster. When the
engine temperature reaches the operating level of
about 120°F (49°C) the PCM removes the ground
from the valve allowing vacuum to flow through the
canister and purges vapors through the throttle body.
During certain Idle conditions, the purge valve may
be grounded to control fuel mixture calibrations.
The fuel tank is sealed with a pressure-vacuum re-
lief filler cap. The relief valve in the cap is a safety
feature, preventing excessive pressure or vacuum in
the fuel tank. If the cap is malfunctioning, and needs
to be replaced, ensure that the replacement is the
identical cap to ensure correct system operation,
OBD-II EVAP System Monitor
Some models have added system components
due to the EVAP system monitor incorporated in the
OBD-II engrne control system. A pressure sensor is
mounted on the fuel tank which measures pressure
inside the tank, and a purge flow sensor measures
the flow of the gases from the canister into the en-
gine.
The PCM can store trouble codes for EVAP sys-
tem performance, a list of the codes is provided later

,
DRIVEABILITYAND EMISSIONS CONTROLS 4-5
Fig. 16 Remove the canister retaining bolts
and remove the canister
Solenoid Valves
u See Figures 17 and 18
1 b Disconnect the negative battery cable.
2. Label and remove the vacuum and electrical
harness connections from the purge control solenoid.
3. Remove the solenoid and mounting bracket
from the engine compartment.
4. Installation is the reverse of the removal proce-
dure.
I
- EVAPORATIVE EMISSION
Fig. 18 location of the evaporative emis-
purge solenoid-1990-93 2.OL DDHC
Volume air flow seneftr I
I Manifold diierential pressure m

&a$34
Fig. 19 Typical EGR system schematie-2.4L engine shown, others similar
IPERATION uum ports; pick one and plug the other. The vacuum
must be retained.
1 See Figure 19
The Exhaust Gas Recirculation (EM) system is
lesigned to reintroduce exhaust gas into the com-
ttii valve.
rustion chambers, thereby lowering combustion b. With 8.5 in. Hg (28.7 kPa) of vacuum or
emperatures and reducing the formation of Oxides of more applied to the valve, air should pass 4. For 1990-93 vehicles. blow air from 1 oas-
sage of the EGR to check condition as foffows--
a. With 1.8 in. Hg (6 kPa) of vacuum or less
aoolied to the valve. air should not oass throuah
litrogen (NO,).
The amount of exhaust gas that is reintroduced
Ito the combustion cycle is determined by several
actors, such as: engine speed, engine vacuum, ex-
raust system backpressure, coolant temperature,
Irottle position. All EGR valves are vacuum oper-
ted. The EGR vacuum diagram for your particular
chicle is displayed on the Vehicle Emission Control
iformation (VECI) label. through the valve.
5. For 1994-00 vehicles, apply vacuum (speci-
fied below) and check the passage of air by blowing
through either side of the EGR passages, as follows:
a. With 1 .?I in. Hg or less of vacuum applied
to the valve, air should blow out of the opposite
passa e.
b. %ith 8.7 in. Hg or more of vacuum applies
to the valve, air should not blow out of the oppo-
:OMPONENTTESTiNG site passage.
6. If the results are not as described, replace the
EGR valve.
iGR Valve
t See Figure 20
1. Remove the EGR valve from the vehicle. Check
I”..““.
:or sticking of plunger caused by excess carbon de-
losits. If such a condition exists, clean with appro- EGR Temperature Lan*nr
u See Figure 21
The EGR temperature sensor is used on California
vehicles only. The EGR temperature sensor detects
Fig. 20 Use a vacuum pump to test the EGR
I I
a coni tance i of water. then measure resis-
I ms the water temperature is increased