check engine light MITSUBISHI ECLIPSE 1991 Owner's Manual

FUEL SYSTEM - Service Adjustment Procedures <1.8L Engine>14-43
(14)lf it is out of specification, adjust by loosing the throttle
position sensor mounting screws and rotating the throttle
position sensor. After adjustment, tighten the screws
firmly.
NOTEClockwise rotation of the throttle position sensor increases
the output voltage.
Throttle position
sensor
t-/ /I
(15)Set the ignition switch at OFF.
(16)Adjust the free play of the accelerator cable.
(17)Reconnect the connectors of the idle speed control servo.
(18)Remove the voltmeter.
(19)Start the engine and check that the engine is running at thecurb idle speed.
Curb idle speed:
700f 100 rpm
(20)Set the ignition switch at OFF, disconnect the negative
battery cable and reconnect it more than
10 seconds later
(By doing so, the memory storing the diagnosis data duringthe idle speed control adjustment is cleared.)
(21)Restart the engine, let it run at idle for about 5 minutes, andcheck that the engine is running in good idle quality.
THROTTLE BODY (THROTTLE VALVE AREA)
CLEANING
NllRCK
(1) Warm up the engine, then stop it.
(2) Remove the air intake hose from the throttle body.
(3) Spray cleaning solvent into the valve through the throttle
body intake port and leave it for about 5 minutes.
(4) Start the engine, race it several times and idle it for about 1minute. If the idling speed becomes unstable slightly open
the throttle valve to keep the engine running.
(5) If the throttle valve deposits are not removed, repeat steps
(3) and (4).
(6) Attach the air intake hose.
(7) Disconnect the battery terminal for
10 seconds or more,
and then reconnect it.
(8) Adjust the idle speed control and throttle position sensor.

14-48FUEL SYSTEM - Service Adjustment Procedures <2.0L Engine>
SERVICE ADJUSTMENT PROCEDURES
<2.0L DOHC Engine>
CURB IDLE SPEED INSPECTION
Caution
N14FHADThe improper setting (throttle valve opening) will increase
exhaust gas temperature at deceleration, reducing
catalys-tic converter life greatly and deteriorating exhaust gas
cleaning performance. It also has effect on fuel ‘consump-
tion and engine braking.
Pre-conditions for inspection
l Engine coolant temperature:
85-95°C (185-205°F)
l Lights, electric cooling fan and accessories: OFF
lTransaxle: Neutral (P for vehicles with automatic transaxle)l Steering wheel: Neutral position (vehicles with a power-
steering)l Check ignition timing and adjust if necessary. Refer to
GROUP 8.
NOTEWith vehicles for Canada, the headlights and taillights, etc.
remain on even when the lighting switch is turned OFF, but thiscauses no problems during inspection.
(1) Connect the tachometer to the engine speed detection
terminal.
(2)Run the engine for more than 5 seconds at an engine speedof 2,000 to 3,000 rpm.
(3) Run the engine at idle for 2 minutes.
(4) Read the idling rpm. If it is not within the specified speed,
check the idle speed control system.
Curb idle speed:
750f 100 rpm
NOTE1. Adjustment of the idling speed is usually unnecessary,
because this system controls the idling speed.
2.For rpm, one-half of the actual engine rpm is indicated,so the actual engine rpm is two times the indicated
value shown by the tachometer.
BASIC IDLE SPEED ADJUSTMENT
N14FHBIPre-conditions for inspection
l Engine coolant temperature:
85-95°C (185-205°F)
l Lights, electric cooling fan, and accessories: OFF
lTransaxle: Neutral (P for vehicles with automatic transaxle)l Steerig wheel: Neutral position (vehicles with a
power-
steering)(1) Connect a tachometer.

FUEL SYSTEM - Service Adjustment Procedures <2.0L Engine>14-51THROTTLE BODY (THROTTLE VALVE AREA)
CLEANINGNl4FtU
(1) Warm up the engine, then stop it.
(2) Remove the air intake hose from the throttle body.
(3) Plug the bypass passage inlet of the throttle body.
CautionDo not allow cleaning solvent to enter the bypass
passage.(4) Spray cleaning solvent into the valve through the throttle
body intake port and leave it for about 5 minutes.
(5) Start the engine, race it several times and idle it for about 1minute. If the idling speed becomes unstable (or if the
engine stalls), slightly open the throttle valve to keep the
engine running.
(6) If the throttle valve deposits are not removed, repeat steps
(4) and (5).
(7) Unplug the bypass passage inlet.
(8) Attach the air intake hose.
(9) Disconnect the battery terminal for 10 seconds or more,
and then reconnect it.
(lO)Adjust the basic idle speed. (Refer to P.14-48.)
RELEASE OF RESIDUAL PRESSURE FROM HIGH
PRESSURE FUEL HOSE
N14FGAFRefer to
P.14-44.FUEL PUMP OPERATION CHECK
N14FDAG(1) Set the ignition switch at OFF.
(2) Check that when the battery voltage is directly applied to
the fuel pump check terminal, the operating sound of the
pump can be heard.
NOTESince the high pressure fuel pump is installed in the fuel
tank, its operating sound cannot be readily heard. Remove
the fuel tank cap and listen to the operating sound through
the filler port.
I(3) Hold the high pressure fuel hose between your fingers and
check that the fuel pressure can be felt.

14-58FUEL SYSTEM -MPI System Inspection <1.8L Engine>
MALFUNCTION INDICATOR LIGHTNWQAB
Among the self-diagnosis items, a malfunction indicator light
comes on to notify the driver of the emission control items
when an irregularity is detected.
However, when an irregular signal returns to
notmal ‘and the
engine control unit judges that it has returned to normal, the
malfunction indicator light goes out.
Moreover, when the ignition switch is turned off, the light goes
out. Even if the ignition switch is turned on again, the light doesnot come on until the irregularity is detected.
Here, immediately after the ignition switch is turn on, the
malfunction indicator light is lit for 5 seconds to indicate that
the malfunction indicator light operates normally.
Items indicated by the lightening malfunction light
Engine control unit
Oxygen sensor
Air-flow sensor
Intake air temperature sensor
Throttle position sensor
Motor position sensor
Engine coolant temperature sensor
Crank angle sensor
No. 1 cylinder TDC sensor
Barometric pressure sensor
Ignition timing adjustment signal
Injector
Fuel pump
EGR system Caution
The malfunction indicator light lights up when the ignition
timing adjustment terminal is short-circuited
,‘t’o ground.
Consequently, it lights up ,when the ignition timing
adjustment is grounded when adjusting ignition timing,
but in this case there is no abnormality.
MALFUNCTION INDICATOR LIGHT INSPECTlON
When turning on the ignition switch, check that the light comes
on.
NOTElf the light does not come on, check the harness and light for
breakage.SELF-DIAGNOSIS
Nl4PMFaThe engine control unit monitors the input/output signals
(some signals at all times and the others under specified
conditions) of the engine control unit.

FUEL SYSTEM - MPI System inspection <1.8L Engine>14-59
--..When it is noticed that an irregularity has continued for a
specified time or longer from when the irregular signal is
initially monitored. Passing a certain number, the engine
control unit judges that an irregularity has occurred, memorizesthe malfunction code, and outputs the signal to the
self-diagnosis output terminal.
There are 14 diagnosis items, and the diagnosis results can beread out with a voltmeter.
Moreover, since memorization of the malfunction codes is
backed up directly by the battery, the diagnosis results are
memorized even if the ignition key is turned off. The malfunc-
tion codes will, however, be erased when the battery terminal
or the engine control unit connector is disconnected.
Caution
If the sensor connector is disconnected with the ignition
switch turned on, the malfunction code is memorized. In
this case, disconnect the battery terminal’
(-) for 10seconds or more, and the diagnosis memory will be
erased.The 14 diagnosis items are provided as follows, and if plural
items are activated, they are all indicated sequentially from thesmallest code number.
perature sensor
CautionFor the malfunction code of the ignition timing adjustment
signal, the light for the ignition timing adjustment terminal
lights up when short-circuited to ground.
Consequently, it is output when the ignition timing
adjustment is grounded when adjusting ignition timing,
but in this case there is not abnormality.
CHECK PROCEDURE (SELF-DIAGNOSIS)N14PCAElPrecautions for Operation
(1) When battery voltage is low, no detection of failure is
possible. Be sure to check the battery for voltage and otherconditions before starting the test.
(2) Diagnosis item is erased if the battery or the engine controlunit connector is disconnected. Do not disconnect the
battery before the diagnosis result is completely read.
(3) After check and correction are over, disconnect ground
cable for
10 seconds or more from negative terminal of
battery and connect it again to make sure that failure code
is erased.

14-72FUEL SYSTEM - MPI Svstem InsDection <2.0L DOHC Engine>
MALFUNCTION INDICATOR LIGHTAmong the self-diagnosis items, a malfunction indicator light
comes on to notify the driver of the emission control items
when an irregularity is detected.
However, when an irregular signal returns to normal and the
engine control unit judges that it has returned to normal. the
malfunction indicator light goes out.
Moreover, when the ignition switch is turned off, the light goes
out. Even if the ignition switch is turned on again, the light doesnot come on until the irregularity is detected.
Here, immediately after the ignition switch is turn on, the
malfunction indicator light is lit for 5 seconds to indicate that
the malfunction indicator light operates normally.
I--l
klfunctionindicator light
Items indicated by the lightening malfunction light
Engine control unit
Oxygen sensor
Air flow sensor
Intake air temperature sensor
Throttle positron sensor
Engrne coolant temperature sensor
Crank angle sensor
Top dead center sensor
Barometric pressure sensor
Detonatron sensor
Injector
Fuel pump
EGR
Ignition co11
/
iMALFUNCTION INDICATOR LIGHT INSPECTION
When turning on the ignition switch, check that the light comes
on.
NOTEIf the light does not come on, check the harness and light for
breakage.

14-84FUEL SYSTEM - Injector
03*0095
Delivery pipe03A0095-SERVICE POINTS OF REMOVAL
H4s0m1‘~
3.DISCONNECTION OF THE HIGH PRESSURE FlJFL HOSE /;;
Bleed the residual pressure within the fuel pipe line’& as to~prevent the flow of fuel.
For information concerning the method to be folfowed for
bleeding the residual pressure, refer to
P.14-44.Caution
Cover the hose connection with rags to prevent splash,
of fuel that could be caused by some residual pressure
in the fuel pipe line.
12. REMOVAL OF DELIVERY PIPE/ 15. INJECTOR
Remove the deliver-y pipe (with the injectors attached to it).Caution
Care must be taken, when removing the delivery pipe,
not to drop the injector.
INSPEiZTION
INJECTORS
N14NGAA
(1) Measure resistance between terminals of injector using a
circuit tester.+-%Standard value:
/13-1652 [at
20°C (68”F)] <1.8L Engine, 2.0L DOHC
Engine
(NoniTurbo)>
2-3Q [at 20°C (68”F)] <2.0L DOHC Engine (Turbo)>
(2) If the resistance is out of specification, replace the injector.
SERVICE POINTS OF INSTALLATION
N14SDAEl’17. INSTALLATION OF
GROMMET/lG. 0-RINGI15. IN-
JECTOR
(I) After installation of the grommet and O-ring (in that
sequence) to the injector, apply light oil or petrol to the
O-ring.(2) While turning the injector to.the left and right, install it
to the delivery pipe.
(3) Check to be sure that the injector turns smoothly.
Caution
If it does not turn smoothly, the O-ring may be
~trapped remove the injector and then re-insert it
into the delivery pipe and check once again.
L

14-98FUEL SYSTEM -Fuel Tank 01
W636
Positioning projection03AO257
\03A0256SERVICE POINTS OF REMOVAL
N14G6AHl6. DISCONNECTION OF HIGH PRESSURE FUEL
HGSECaution
Cover the hose connection with rags to prevent splash
of fuel that could be caused by some residual pressure
in the fuel pipe line.
INSPECTIONN14GCAHl Check the hoses and the pipes for crack or damage.
l Check the fuel tank cap for malfunction.
l Check the fuel tank for deformation, corrosion or crack.
l Check the fuel tank for dust or foreign material.
NOTE
If the inside of the fuel tank is to be cleaned, use any one ofthe following:
(1) Kerosene
(2) Trichloroethylene
(3) A neutral emulsion type detergent
OVERFILL LIMITER (TWO-WAY VALVE)
Set a hand vacuum pump at inlet side or outlet side; the valve
is good if, when a negative pressure (vacuum) is applied, air
flows after a slight negative pressure is initially maintained.
SERVICE POINTS OF INSTALLATION
N14GDAO16. INSTALLATION OF FUEL PUMP AND FUEL GAUGE
UNIT ASSEMBLY
Align the three positioning projections of the packing with
the holes in the fuel pump and fuel gauge unit assembly.
12. INSTALLATION OF HOLE COVER
) Before installing the hole cover, apply the specified
sealant to the rear floor pan.
Specified sealant: MOPAR Rope Caulk Sealer
3116
x 80” roll Part No.4026044 or
equivalent
!) After installing the fuel pump and fuel gauge assembly,
start the engine and check to ensure that there is no
fuel leakage.