1991 MITSUBISHI ECLIPSE check engine light

_-
a--ENGINE
<2.0L DOHC Engine> -Service Adjustment Procedures9-75
JMANIFOLD VACUUM INSPECTION
NO9FNAO(1) Before inspection and adjustment, put the vehicle into the
following state.
l Engine coolant temperature:
85-g5”C (185-205°F)
l Lights, electric, cooling fan, and accessories: OFF
lTransaxle: Neutral (N or
P for vehicles with an automa-
tic transaxle)
l Steering wheel: Neutral position
(2) Check that the idling revolution speed is normal.
(3) Remove the PCV hose from the PCV valve and attach a
vacuum gauge.
(4) Check that the negative pressure at the intake manifold
during idle revolution is normal.
Standard value:: 490
mmHg (19.3 in.Hg): 480
mmHg (18.9 in.Hg)(5) If outside the standard value, isolate the cause by referring
to the following table and repair the fault.
ymptomICause1 Remedy
The vacuum gauge reading is less than
standard value, but the pointer is
stable.
The vacuum gauge pointer swingsslowly.
l Ignition timing is retarded.
l Air mixture concentration too
rich.
l Adjust the ignition timing.
l Check ECI-MULTI system.
The vacuum gauge pointer drops
irre-gularly.l Air mixture concentration too
lean.
l Check ECI-MULTI system.
The vacuum gauge pointer drops inter-mittently to 30 to 160
mmHg (1.2 to
6.3 in.Hg).
The vacuum gauge pointer drops sud-
denly from the normal reading to 250
mmHg (9.8 in.Hg), then returns tonormal.
l Incomplete close contact of in-
take and exhaust valve seat.
l Broken cylinder head gasket
l Check and repair the valve.
l Replace cylinder head gasket.

9-106ENGINE <2.0L DOHC Engine> - Timing Belt. ADJUSTMENT OF TIMING BELT TENSION
(1) After turning the crankshaft
l/4 turn counterclockwise,.5;;turn it clockwise to move the No. 1 cylinder to top dead
center.(2) Loosen the center bolt, and then, as shown in the
illustration, attach the special tool and a torque wrench
and apply a torque of 2.6-2.8 Nm
(1.88-2.03 ft.lbs.).If the body interferes with the special tool and the
torque wrench, use a jack to slightly raise the engine
assembly.
NOTEUse a torque wrench that is capable of measurement
within a range of
O-3 Nm (O-2.2 ft.lbs.).(3) Holding the tensioner pulley with the special tool and
torque wrench, tighten the center bolt to specification.
(4) Screw the special tool into the engine left support
bracket until its end makes contact with the tensioner
arm. At that point, screw the special tool in some more
and then remove the set wire attached to the auto
tensioner.(5) Remove the special tool.
(6) Rotate the crankshaft two complete turns clockwise
and leave it as is for about 15 minutes. Then, measure
the auto tensioner protrusion “A” (distance between
the tensioner arm and auto tensioner body) to ensure,.+
that it is up to specification.
Standard value:
3.8-4.5 mm (.15-.18 in.)
If it is out of specification, repeat steps (6) through (1)
until the specified value is obtained.
(7) If the clearance between the tensioner arm and the
auto tensioner body cannot be measured (when the
engine is being mounted, etc.), the following proce-
dures can be used to substitute for the ordinan/ methodof measurement.
@ Screw in the special tool until it contacts the
tensioner arm.
@ From that point of contact, further screw in the
special tool, screwing it in until the push rod of the
auto tensioner body is caused to move backward
and the tensioner arm contacts the auto tensioner
body.Check to be sure that the amount that the special
tool has been screwed in (when the push rod
moves backward) is the standard value.
Standard value: 2.5-3 turns

9-120ENGINE <2.0L DOHC Engine>- Front Case, Oil Pump and Silent Shaft
7LUOoo6
Fine
7LUOOO76LUO12OIL PRESSURE SWITCH
-1
(1) Connect a tester (ohm range) between the terminal and thebody and check for conductivity. If there is no conductivity,
replace the switch.
(2) Next insert a very fine wedge through the oil hole, pushing
it slightly. There should be no conductivity (resistance
should be infinite). If there is conductivity even when
wedge is pushed, replace the switch.
(3) Or, if there is no conductivity when a 50
kPa (71 psi)
pressure is placed through the oil hole, the switch is
operating properly. Check at this time to see that there is
no air pressure leakage. If there is air pressure leakage, thediaphragm is broken, and the switch should be replaced.
OIL COOLER BYPASS VALVE (Turbo)
NaacNA
(1) Make sure that the valve moves smoothly.
(2) Ensure that the dimension
L measures the standard value
under normal temperature and humidity.
Dimension
L: 34.5 mm (1.358 in.)
(3) The dimension must be the standard value when measuredafter the valve has been dipped in
100°C (212°F) oil.
Dimension
L: 40 mm (1.57 in.) or more
OIL PUMP
NOBRCGG(1) Assemble the oil pump gear to the front case and rotate it
to ensure smooth rotation with no looseness.
(2) Ensure that there is no ridge wear on the contact surface
between the front case and the gear surface of the oil
pump cover.
(3) With the drive and driven gears installed into the front case.Standard value:
Drive gear
0.16-0.21 mm (.0063-.0083 in.)
Driven gear
0.13-0.18 mm (.0051-.0071 in.)
Limit:
Drive gear0.25 mm
(.0098 in.)
Driven gear0.25 mm
(4098 in.)
k

9-128ENGINE <2.0L DOHC Enaine> - Piston and Connectina Rod
DEN050
6EN185
95EN057
Piston ringring gap6EN037
JSERVICE POINTS OF DISASSEMBLY
NOSTFAC2. REMOVAL OF CONNECTING ROD CAP
Mark the large end of the connecting rod with the cylinder
number for use during reassembly.
7. REMOVAL OF NO. 1 PISTON RING
/8. NO.2 PISTON
RINGRemove the piston rings with a piston expander.
INSPECTION
PISTONNO@lCAFReplace the piston if scratches or seizure is evident on its
surfaces (especially the thrust surface). Replace the piston if it
is cracked.PISTON PIN
(1) Insert the piston pin into the piston pin hole with a thumb.
You should feel a slight resistance. Replace the piston pin ifit can be easily inserted or there is an excessive play.
(2) The piston and piston pin must be replaced as an assembly.PISTON RING
NOSTCBF
(1) Check the piston ring for damage, excessive wear, and
breakage and replace if defects are evident. If the piston
has been replaced with a new one, the piston rings must
also be replaced with new ones.
(2) Check the clearance between the piston ring and ring
groove. If the limit is exceeded, replace the ring or piston,
or both.
Standard value: 0.03-0.07 mm
(.0012-.0028 in.)
Limit: 0.1 mm
(.004 in.)
(3) Install the piston ring into the cylinder bore. Force it down
with a piston, its crown being in contact with the ring, to
correctly position it at right angles to the cylinder wall.
Then, measure the end gap with a feeler gauge.
If the ring gap is excessive, replace the piston ring.
Standard value:
No. 10.25-0.40 mm (.0098-.0157 in.)
No.20.20-0.35 mm (.0079-.0138 in.)
Oil0.20-0.70 mm (.0079-.0276 in.)
Limit:
No. 1,
No.20.8 mm (.031 in.)
Oil1.0 mm (.039 in.)

14-IFUEL SYSTEM
CONTENTS
AUTO-CRUISECONTROLSYSTEM...........................................109AUTO-CRUISECONTROL.......................................................140SERVICEADJUSTMENTPROCEDURES..............................135Accelerator Cable, Throttle Cable and Auto-cruise
ControlCableInspectionandAdjustment........................136Auto-cruise
ControlSystemInspection.............................135lndrvrdualPartsInspection..................................................137SPECIFICATIONS.....................................................................109GeneralSpecifications.......................................................109ServiceSpecifications
.........................................................109Torque Specrfications..........................................................109TROUBLESHOOTING...............................................................110Auto-CruiseControlCircurt................................................128Auto-cruise
ControlComponentsLocation........................126Auto-cruise Control Related Harnesses
.............................125Check Chart
........................................................................114Input Check.........................................................................123Self-diagnosis
Check..........................................................121Troubleshootrng
Quick-referenceChart..............................110ENGINECONTROL.......................................................................105ENGINECONTROL..................................................................107--SERVICEADJUSTMENTPROCEDURES..............................106Accelerator Cable Inspection and Adjustment..................106Accelerator Switch Inspectron and Adjustment................106SPECIFICATIONS.....................................................................105Lubricants.............................................................................105Sealant.................................................................................105ServiceSpecifications
..........................................................105TorqueSpecifications..........................................................105TROUBLESHOOTING...............................................................105FUELSYSTEM..............................................................................2FUELFILTER............................................................................104FUELLINEANDVAPORLINE..............................................102FUEL PUMP, FUEL GAUGE UNIT ANDOVERFILL LIMITER(TWO-WAY VALVE).............101FUEL PUMP, FUEL GAUGE UNIT ANDOVERFILL LIMITER (TWO-WAY VALVE).............99FUELTANK.............................................................97FUELTANK..............................................................93INJECTOR.................................................................................83MPISYSTEMINSPECTION<1.8LEngine>.......................56AirConditioner
Switch........................................................64Air Conditioner Power Relay
..............................................67Components
Location......................................................56
ControlRelay
.................................................................66EGRControlSolenoidValve...............................................67EGRTemperatureSensor..................................................64Engine Coolant Temperature Sensor
.................................62IdlePosrtionSwitch
...........................................................63IdleSpeedControlServo
.............................
....................65InhibitorSwitch....................................................................65hjeCtOrS................................................................................65IntakeAirTemperatureSensor..........................................6’2MalfunctionlndtcatorLight
..........................................58MotorPosition
Sensor................................................63OxygenSensor
.................................................................64Power Steering 011 Pressure Swatch...........................65PowerTransistor
................................................................67PurgeControlSolenoidValve.........................................67
Self-Diagnosis.......................................................................
ThrottlePositronSensor.....................................................
Vehicle Speed Sensor.........................................................MPI
SYSTEMINSPECTION<2.0L DOHCEngine>...........Air Conditioner Power Relay..............................................
Arr Conditioner Swatch........................................................
Components Location
.........................................................
Control
Relay.......................................................................
EGR Control Solenoid Valve...............................................
EGR Temperature Sensor
...................................................
Engine Coolant Temperature Sensor
.................................Fuel Pressure Control Valve...............................................
Idle Position Switch
............................................................
Idle
SpeedControlServo...................................................Injectors
................................................................................
Intake Air Temperature Sensor..........................................
Malfunction Indicator Light.................................................
Oxygen Sensor
....................................................................
Power
Steering
OilPressureSwitch.................................Power Transistor
.................................................................
Purge Control Solenoid Valve.............................................
Self-Diaanosis.......................................................................
58
63
2382
79
688182
79
7682
77
79
79
76
727879
82
8273ThrottletiPosition Sensor
.....................................................77Vehicle Speed Sensor
.........................................................79SERVICE ADJUSTMENT PROCEDURES<1.8L Engine>........................................................................41Curb Idle Speed Inspection
................................................41EGR Valve Control Vacuum Check....................................47Fuel Pressure Test
..............................................................44Fuel Pump Operation Check
..............................................44Idle Speed Control and Throttle Position
Sensor Adjustment
..............................................................
41Purge Port Vacuum Check
.................................................47Release of Residual Pressure from
High Pressure Fuel Hose
...................................................
44Throttle
Body(Throttle Valve Area)Cleaning....................43SERVICE ADJUSTMENT PROCEDURES<2.0LDOHCEngine>............................................................48Basic Idle Speed Adjustment
.............................................
48
Curb Idle Speed Inspection
................................................48EGR Valve Control Vacuum Check....................................55Fuel Pressure Test
..............................................................52Fuel Pump Operation Check
..............................................51Idle Position Switch Adjustment........................................52Purge Port Vacuum Check
.................................................55Release of Residual Pressure from
High Pressure Fuel Hose
...................................................51Throttle Body (Throttle Valve Area) Cleaning....................51ThrottlePositionSensorAdjustment.................................50SPECIALTOOLS......................................................................6SPECIFICATIONS.....................................................................2GeneralSpecifications.........................................................2Sealant and Adhesive
.........................................................5Service Specifications
..........................................................4Torque Specifications
..........................................................5THROlTLEBODY<1.8LEngine>........................................85THROlTLE BODY <2.0L DOHC Engine>............................89TROUBLESHOOTING...............................................................6

FUEL SYSTEM - Service Adjustment Procedures <1.8L Engine>l-4-41
SERVICE ADJUSTMENT PROCEDURES

CURB IDLE SPEED INSPECTION
CautionNlIFiiAE
The improper setting (throttle valve opening) will increase
exhaust gas temperature at deceleration, reducing catalystlife greatly and deteriorating exhaust gas cleaning per-
formance. It also has effect on fuel consumption and
engine braking.
ilter
Paper clip
16A0898
PI-e-conditions for inspection
0Engine coolant temperature: 85-95°C (185-205°F)
0Lights, electric cooling fan and accessories: OFF
l Transaxle: Neutral
(P for vehicles with an 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) Insert the paper clip to the connector.
(2) Connect the tachometer to the inserted clip.
(3)Run the engine for more than 5 seconds at an engine speedof 2,000 to 3,000 rpm.
(4) Run the engine at idle for 2 minutes.
(5) Read the idling rpm. If it is not within the specified speed,
check the idle speed control system.
Curb idle speed: 700
f 100 rpm
NOTEAdjustment of the idling speed is usually unnecessary,
because this system controls the idling speed.
IDLE SPEED CONTROL AND
THROTlLE POSI-
TION SENSOR ADJUSTMENT
N14FIATAdjustment conditions
l Engine coolant temperature:
85-95X (185-205°F)
l Lights, electric cooling fan and accessories: Set to OFF
l Transaxle: Neutral (P for vehicles with an automatic
transaxle)l Steering wheel: Neutral position (vehicles with a power
steering)
(1) Slacken the accelerator cable enough.
(2) Connect a tachometer.