check engine light ACURA TL 1995 Service Repair Manual

Hydraulic Tappets

Valve Installation

When installing valves in the cylinder head, coat the

valve stems with oil before inserting them into the valve

guides. Make sure the valves move up and down

smoothly.

When the valves and springs are in place, lightly tap the

end of each valve stem two or three times with a plastic

mallet to ensure proper seating of the valve and valve

keepers.

NOTE:

Make sure that the valve keepers are properly posi-

tioned on the valve stem.

Tap the valve stem only along its axis so you do not

bend the stem.

PLASTIC MALLET
Bleeding

VALVE STEM ENDS
1. Fill a container with 10W - 30 engine oil and place

the hydraulic tappet in it. Press down on the check

ball with a thin wire. Bleed the tappet of air by

pumping the plunger slowly until no bubbles come

out of the hydraulic tappet.

WIRE

PLUNGER

10W —30

ENGINE OIL
HYDRAULIC

TAPPET

CHECK BALL

2. Install the hydraulic tappet to the rocker arm.

NOTE:

Use a new O-ring when reassembling.

Apply oil to the O-ring before installation.

ROCKER ARM

O-RING

Replace.

HYDRAULIC

TAPPETProCarManuals.com

Cylinder Heads

Installation (cont'd)

6. Install the head cover gasket in the groove of the

cylinder head cover. Seat the recesses for the cam-

shaft first, then work it into the groove around the

outside edges.

NOTE:

Before installing the cylinder head cover gasket,

thoroughly clean the seal and the groove.

When installing, make sure the head cover gasket

is seated securely in the corners of the recesses

with no gap.

CORNERS OF

THE RECESS
HEAD COVER

GASKET

Clean.
CORNERS OF

THE RECESS

7.
CYLINDER

HEAD COVER

Apply liquid gasket to the head cover gasket at the

four corners of the recesses.

NOTE:

Use liquid gasket, Part No. 08718 - 0001 or 08718

-003.

Check that the mating surfaces are clean and dry

before applying liquid gasket.

Do not install the parts if five minutes or more have

elapsed since applying liquid gasket. Instead, reap-

ply liquid gasket after removing old residue.

After assembly, wait at least 30 minutes before

filling the engine with oil.

Apply liquid gasket to

the shaded areas.
8.
When installing the cylinder head cover, hold the

head cover gasket in the groove by placing your fin-

gers on the camshaft contacting surfaces (top of the

semicircles).

Once the cylinder head cover is on the cylinder head,

slide the cover slightly back and forth to seat the

head cover gasket.

NOTE:

Before installing the cylinder head cover, clean

the cylinder head contacting surfaces with a

shop towel.

Do not touch the parts where liquid gasket was

applied.

Replace the washer when damaged or deterio-

rated.

WASHER

CYLINDER

HEAD COVER

9. Tighten the nuts in two or three steps. In the final step,

tighten all nuts, in sequence, to 12 N-m (1.2 kgf-m,

8.7 Ibf-ft).

NOTE: After assembly, wait at least 30 minutes

before filling the engine with oil.ProCarManuals.com

PGM-FI System

System Description (cont'd)

3. Fuel Cut-off Control

During deceleration with the throttle valve closed, current to the fuel injectors is cut off to improve fuel economy at

speeds over 1,000 rpm.

Fuel cut-off action also takes place when engine speed exceeds 6,500 rpm, regardless of the position of the throttle

valve, to protect the engine from over-revving.

4. A/C Compressor Clutch Relay .

When the PCM receives a demand for cooling from the air conditioning system, it delays the compressor from being

energized, and enriches the mixture to assure a smooth transition to the A/C mode.

5. Evaporative Emission (EVAP) Purge Control Solenoid Valve

'96 model: When the engine coolant temperature is below 158°F (70°C), the PCM controls the EVAP purge control

solenoid valve which cuts vacuum to the EVAP purge control canister diaphragm.

'97 - 98 models: When the engine coolant temperature is above 99°F (37°C), the PCM controls the EVAP purge control

solenoid valve which controls vacuum to the EVAP purge control canister.

6. Intake Air Bypass (IAB) Low Control Solenoid Valve, Intake Air Bypass (IAB) High Control Solenoid Valve

When engine speed is below 3,350 rpm, the IAB High Control Solenoid Valve and IAB Low Control Solenoid Valve are

activated by a signal from the PCM. Intake air flows through a long chamber path, increasing torque at low RPM.

When engine speed is 3,350 - 3,950 rpm, the IAB Low Control Solenoid Valve is deactivated by the PCM. Intake air

flows through a short chamber path, increasing mid-range torque.

When the engine rpm is above 3,950 rpm, the IAB Low Control Solenoid Valve and IAB High Control Solenoid Valve are

deactivated by the PCM. This creates a very short intake path and increases high-speed torque.

7. Exhaust Gas Recirculation (EGR) Control Solenoid Valve

When the EGR is required for control of oxides of nitrogen (NOx) emissions, the PCM controls the EGR control solenoid

valve which supplies regulated vacuum to the EGR valve.

ECM Fail-safe/Back-up Functions

1. Fail-safe Function

When an abnormality occurs in a signal from a sensor, the PCM ignores that signal and assumes a pre-programmed

value for that sensor that allows the engine to continue to run.

2. Back-up Function

When an abnormality occurs in the PCM itself, the fuel injectors are controlled by a back-up circuit independent of the

system in order to permit minimal driving.

3. Self-diagnosis Function [Malfunction Indicator Lamp (MIL)]

When an abnormality occurs in a signal from a sensor, the PCM supplies ground for the MIL and stores the DTC in

erasable memory. When the ignition is initially turned on, the PCM supplies ground for the MIL for two seconds to

check the MIL bulb condition.

4. Two Driving Cycle Detection Method

To prevent false indications, the two driving cycle detection method is used for the H02S, fuel metering-related, idle

control system, ECT sensor, EGR system, TWC, EVAP control system and other self-diagnostic functions. When an

abnormality occurs, the PCM stores it in its memory. When the same abnormality recurs after the ignition switch is

turned OFF and ON (II) again, the PCM informs the driver by lighting the MIL.

However, to ease troubleshooting, this function is cancelled when you short the service check connector. The MIL will

then blink immediately when an abnormality occurs.ProCarManuals.com

Powertrain Control Module (PCM)

NOTE: If this symptom is intermittent, check for a loose fuse No. 1 (BACK UP

LIGHTS, METER LIGHTS, 10 A) in the under-dash fuse/relay box, a poor con-

nection at PCM terminal A7, or an intermittent open in the GRN/RED wire

between the PCM (A7) and the gauge assembly.

Is the low oil pressure light on?

Try to start the engine.

Does the engine start?

Check for an open in the wire or

bulb (MIL line):

1. Turn the ignition switch OFF.

2. Connect the PCM connector ter-

minal A7 to body ground with a

jumper wire.

3. Turn the ignition switch ON (II).

Is the MIL on?

Substitute a known-good PCM,

and recheck. If symptom/indica-

tion goes away, replace the origi-

nal
PCM.
— Repair short or open in the

wire between NO. 1 (BACK-UP

LIGHTS, METER LIGHTS) (10

A) fuse and gauge assembly.

— Replace No. 1 (BACK-UP

LIGHTS, METER LIGHTS) (10 A)

fuse.

PCM CONNECTOR A (26P)

Check for an open in the wires

(PG1, PG2 lines):

1. Turn the ignition switch ON (II).

2. Measure voltage between

body ground and PCM con-

nector terminals A12 and A25

individually.
Wire side of female terminals

Is there less than 1.0 V?
Repair open in the wire(s)

between PCM and G101 (located

at intake manifold) that had

more than 1.0 V.

PCM CONNECTOR A (26P)

JUMPER WIRE

Wire side of female terminals
Repair open in the wires

between PCM (A7) and gauge

assembly.

Replace the MIL bulb.
Substitute a known-good PCM

and recheck. If symptom/indica-

tion goes away, replace the origi-

nal
PCM.
Turn the ignition switch ON (II).
The Malfunction Indicator Lamp

(MIL) never comes on (even for

two seconds) after ignition is

turned on (II).ProCarManuals.com

Idle Contro l Syste m
Alternato r (ALT ) F R Signa l
This signal s th e PC M whe n th e Alternato r (ALT ) i s charging .
Is ther e approx . 5 V ?
Chec k th e operatio n o f th e ALT :
1 . Tur n th e ignitio n switc h OFF .
2 . Reconnec t th e AL T GR N 4 P
connecto r t o th e ALT .
3 . Star t th e engine . Hol d th e
engin e a t 3,00 0 rp m wit h n o
loa d (transmissio n in o r
position ) unti l th e radiato r fa n
come s on , the n le t i t idle .
4 . Measur e voltag e betwee n PC M
connecto r terminal s D 5 an d A26 .
Doe s th e voltag e decreas e whe n
headlight s an d rea r defogge r ar e
turne d on ?
Chec k fo r a n ope n in th e wir e (AL T
F line) :
1 . Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e negativ e bat -
ter y cabl e fro m th e battery .
3 . Disconnec t th e PC M connec -
tor D (22P) .4. Disconnec t th e GR N 4 P con -
necto r fro m th e ALT .
5 . Connec t th e AL T 4 P connecto r
termina l No . 2 to bod y groun d
with a jumpe r wire .6. Chec k fo r continuit y betwee n
bod y groun d an d PC M con -
necto r termina l D5 .
I s ther e continuity ?
Se e th e AL T inspectio n (se e
sectio n 23 ).
PC M CONNECTOR S
A (26P)D (22P )
LG1 (BRN/BLK )
Wire sid e o f femal e terminal s
Chec k fo r a shor t i n th e wir e (AL T
F line) :1. Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e negativ e bat -
ter y cabl e fro m th e battery .
3 . Disconnec t th e PC M connecto r
D (22P) .4. Chec k fo r continuit y betwee n
bod y groun d an d PC M con -
necto r termina l D5 .
D (22P )
Is ther e continuity ? Repai
r shor t i n th e wir e betwee nthe PC M (D5 ) and th e ALT .
Substitut e a known-goo d PC M
an d recheck . I f prescribe d voltag e
i s no w available , replac e th e origi -
nal PCM .
ALT F R signa l i s OK .
ALT GR N 4P CONNECTO R (C129 )
JUMPE R WIR E
Wir e sid e o f femal e terminal s
Repai r ope n wir e betwee n th e
PC M (D5 ) and th e ALT .
Wire sid e o f femal e terminal s
PC
M CONNECTO R D (22P )
Chec
k fo r a shor t i n th e wir e (AL T
F line) :
1 . Disconnec t th e GR N 4 P con -
necto r fro m th e ALT .
2 . Tur n th e ignitio n switc h O N (II) .
3 . Measur e voltag e betwee n PC M
connecto r terminal s D 5 an d A26 .
Inspectio
n o f AL T F R Signal .
ProCarManuals.com

Idle Contro l Syste m
Idle Spee d Settin g
Inspection/Adjustmen t
NOTE:
Before settin g th e idl e speed , chec k th e followin g
items :
— Th e MI L ha s no t bee n reporte d on .
— Ignitio n timin g
— Spar k plug s
— Ai r cleane r (ACL )
— PC V syste m
(Canada ) Pul l th e parkin g brak e leve r up . Star t th e
engine , the n chec k tha t th e headlight s ar e off .
1 . Star t th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
no loa d (transmissio n i n o r position ) unti l th e
radiato r fa n come s on , the n le t i t idle .
2 . Connec t a OBDI I sca n too l (se e pag e 11-32 ) o r
tachometer .
• Connec t a tachomete r t o th e ignitio n contro l
module (ICM ) secondary , or.. .
TACHOMETE R
ICM
Remov e th e rubbe r ca p fro m th e tachomete r
connecto r an d connec t a tachometer .
TACHOMETE R TACHOMETE R
CONNECTOR
RUBBERCAP
3. Disconnec t th e IA C valv e connector .
4.
5 .
IA C VALV E
Start th e engin e wit h th e accelerato r peda l slightl y
depressed . Stabiliz e th e rp m a t 1,000 , the n slowl y
releas e th e peda l unti l th e engin e idles .
Check idlin g in no-loa d conditions : headlights , blow -
er fan , rea r defogger , radiato r fan , an d ai r conditione r
ar e no t operating .
Idl e spee d shoul d be :
480 5 0 rp m
(in o r position )
Adjus t th e idl e speed , i f necessary , b y turnin g th e
idl e adjustin g screw .
NOTE : Afte r adjustin g th e idl e spee d i n thi s step ,
rechec k th e ignitio n timin g (se e sectio n 23 ).
I f i t i s ou t o f spec , g o bac k t o ste p 4 .
IDL E ADJUSTIN G SCRE W
ProCarManuals.com

Intake Ai r Syste m
Throttl e Bod y
Descriptio n
The throttl e bod y i s a single-barre l side-draf t type . Th e
lowe r portio n o f th e throttl e valv e i s heate d b y engin e
coolan t fro m th e cylinde r head . Th e idl e adjustin g screw ,
whic h increases/decrease s bypas s air , an d th e Evapora -
tiv e Emissio n (EVAP ) Contro l Caniste r por t ar e locate d o n
the to p o f th e throttl e body .
THROTTL EPOSITION(TP)SENSO R
IDLE ADJUSTIN GSCREW
THROTTL E
VALV E
THROTTLE
STOPSCRE W
(non-adjustable )
Inspection
CAUTION : D o no t adjus t th e throttl e sto p screw . I t i s
prese t a t th e factory .
1 . Disconnec t th e vacuu m hos e (t o th e EVA P contro l
canister ) fro m th e to p o f th e throttl e body ; connec t
a vacuu m gaug e t o th e throttl e body .
2 . Star t th e engine . Hol d th e engine at 3,00 0 rp m wit h
no loa d (transmissio n i n ! o r position ) unti l th e
radiato r fa n come s on , the n le t i t idle .
VACUU M PUMP/GAUG EA973X - 04 1 - XXXX X
3. Allo w th e engin e t o idle , an d chec k tha t th e gaug e
indicate s n o vacuum .
If ther e i s vacuum , chec k th e throttl e cabl e (se e
pag e 11-135 ).
4 . Chec k tha t vacuu m is indicate d o n th e gaug e whe n
the throttl e is opene d slightl y fro m idle .
If th e gaug e indicate s n o vacuum , chec k th e throt -
tl e bod y port . I f th e throttl e bod y por t i s clogged ,
clea n i t wit h carbureto r cleaner .
5 . Sto p th e engine , an d chec k tha t th e throttl e cabl e
operates smoothly without bindin g o r sticking .
I f ther e ar e an y abnormalitie s i n th e abov e steps ,
check for .
— Excessiv e wea r o r pla y i n th e throttl e valv e shaft .
— Stick y o r bindin g throttl e leve r a t ful l close posi-
tion.
— Clearanc e betwee n throttl e sto p scre w an d throt -
tl e leve r a t ful l clos e position .
There shoul d b eno clearance .THROTTLE LEVE R
THROTTL ELEVER
THROTTL E STO P SCRE W(Non-adjustable )
Replace th e throttl e bod y i f ther e is excessiv e pla y i n th e
throttl e valv e shaf t o r i f th e shaf t i s bindin g o r sticking .
ProCarManuals.com

Emission Control System

Positive Crankcase Ventilation (PCV) System

Description

The Positive Crankcase Ventilation (PCV) system is

designed to prevent blow-by gas from escaping to the

atmosphere. The PCV valve contains a spring-loaded

plunger. When the engine starts, the plunger in the PCV

valve is lifted in proportion to intake manifold vacuum and

the blow-by gas is drawn directly into the intake manifold.

INTAKE

MANIFOLD
BREATHER PIPE

PCV HOSE

PCV VALVE

BLOW-BY VAPOR

FRESH AIR
Inspection

1. Check the PCV hoses and connections for leaks and

clogging.

PCV HOSE

BREATHER

PIPE

PCV VALVE

2.
At idle, make sure there is a clicking sound from the

PCV valve when the hose between the PCV valve

and intake manifold is lightly pinched with your fin-

gers or pliers.

Gently pinch here

If there is no clicking sound, check the PCV valve

grommet for cracks or damage. If the grommet is

OK, replace the PCV valve and recheck.ProCarManuals.com

19. Turn the ignition switch ON (II). Move the shift lever

through all gears, and check the A/T gear position

switch synchronization with the A/T gear position

indicator.

GAUGE ASSEMBLY

20. If the A/T gear position switch is not synchronized

with the A/T gear position indicator, loosen the bolts

securing the A/T gear position switch and adjust the

A/T gear position switch installation.

21. Start the engine. Move the shift lever through all

gears, and verify the following:

• The shift lever cannot be moved to the posi-

tion from the position without pushing the

shift lever.

• The engine will not start in any gear, only in the

or position.

• The back-up lights come on when the shift lever

is in the position.
A/T GEAR POSITION

INDICATORProCarManuals.com

Symptom-to-Component Chart

Hydraulic System

SYMPTOM

Engine runs, but vehicle does not move in any gear.

Vehicle moves in , but not in , , or position.

Vehicle moves in , , but not in position.

Vehicle moves in , , but not in position.

Vehicle moves in but not in position.

Vehicle moves in position.

Excessive idle vibration

Poor

acceleration; flares on starting off in position

Stall rpm high in position

Stall rpm high in , , position

Stall rpm high in position

Stall rpm high in position

Stall rpm low

No shift

Fails to shift in position; from 1st to 3rd gear

Fails to shift in position; from 1st to 4th gear

Erratic upshifting

1-2 upshift, 2-3 upshift, 3-4 upshift

1-2 upshift

2-3 upshift

3-4 upshift

Harsh upshift (1-2)

Harsh upshift (2-3)

Harsh upshift (3-4)

Harsh downshift (2-1)

Harsh downshift (3-2)

Harsh downshift (4-3)

Flares on 3-4 upshift

Excessive shock on 2-3 upshift

Excessive shock on 3-4 upshift

Late
shift from position to or positions

Late shift from position to position

Noise from transmission in all shift lever positions

Vehicle does not accelerate more than 31 mph (50 km/h).

Shift
^ver
does
not
operate smoothly.

Fails to shift; stuck in 4th gear

Transmission will not shift into parking gear in position.

Stall
rpm high; all clutch pressures are in specification.

Lock-up clutch does not disengage.

Lock-up clutch does not operate smoothly.

Lock-up clutch does not engage.

No engine braking in position

No engine braking in position

Vibration in all positions

Position indicator light does not come on
Check these items on the

PROBABLE CAUSE List

1,2,3,4,5,6,7,37,42

5, 8, 9, 59, 60, 61
('96)

5, 10,
11,60

5,12,58

5, 9, 59

9,11,13,31,32,34,35,36

2, 33, 37, 48, 49

1, 2, 3, 5, 42, 45

5, 7, 9, 59

5,11,60

58

14, 33, 48, 49

41,51,52

19

19,20

45,64

51

52

51

11, 16, 17, 18, 21, 27, 59, 60, 61C97 - '98),

62C97 - '98), 63, 64

16, 17, 19, 22, 31, 60, 61C97 - '98), 62C97 - '98),

63,64

16, 17, 20, 22, 23, 28, 29, 30, 32, 61C97 - '98),

62C97 - '98), 63, 64

9, 27, 28, 59

19, 22, 29, 39

16, 17, 20, 22, 23, 24, 30, 40, 56, 61('97 - '98),

62C97 - '98), 63, 64

16, 17, 20, 22, 23, 25, 28, 30, 32, 61('97 - '98),

62C97 - '98)

16, 17, 22, 39, 46, 61C97 - '98), 62C97 - '98), 64

16, 17, 22, 23, 28, 29, 40, 46, 61
('97
-
'98),

62C97 - '98), 64

3, 9, 26

3, 18, 58

2, 4, 7, 41

14

5,43

17,51,52

5,
15,43

45

16, 17, 47, 48, 49, 50, 53, 54, 64

16, 17, 45, 47, 48, 49, 50, 53, 54, 64

16, 17, 45, 47, 48, 49, 50, 53, 54, 63, 64

7, 9, 51, 57

7, 11,51,57,59

37

5, 43, 55
Check these items

on the NOTES List

K, L, R, S

C, M, 0

C, L

C, L, Q

C, L, M

C, D

B, K, L

K, L, R

C, D

C, D

N

R

G, L

V

C, D, E, V

C, D, E, H, L, V

C, D, E, I, L, V

0

C, D, E, H

C, D, E, I

E, L, N, V

E, L, N

E, L, N

M

Q

K, L, Q

P

P

D, K, O

E, L, V

L

E, L, V

C, D

C, DProCarManuals.com