1991 MITSUBISHI ECLIPSE engine coolant

FUEL SYSTEM - Service Adjustment Procedures <1.8L Engine>14-47
A
E3x>
/ )Engine speed
(rpm)1 FU446Engine speed (rpm)
>3FU262EGR VALVE CONTROL VACUUM CHECK

Check ConditionEngine coolant temperature: 85-‘95”C (185-205°F)
(1) Disconnect the vacuum hose from the throttle body EGR
vacuum nipple and connect a hand vacuum pump to the
nipple.(2) Start the engine and check to see that, after raising the
engine speed by racing the engine, vacuum raises pro-
portionately with the rise in engine speed.
NOTEIf there is a problem with the change in vacuum, it is
possible that the throttle body port may be clogged and
require cleaning.
PURGE PORT VACUUM CHECKCheck ConditionN14FvBcEngine coolant temperature:
85-95°C (185-205°F)
(1) Disconnect the vacuum hose from the throttle body purge
hose nipple and connect a hand vacuum pump to the
nipple.(2) Start the engine and check to see that, after raising the
engine speed by racing the engine, vacuum remains fairly
constant.NOTE
If there is no vacuum created, it is possible that the throttlebody port may be clogged and require cleaning.

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>14-55
(18)Connect the high-pressure fuel hose,,to the delivery pipe
and tighten the screws to the specified torque.
(19)Check for fuel leaks.
@I Apply battery voltage to the fuel pump check terminal
to operate the fuel pump.
@ With fuel pressure acting, check the fuel line for leaks.
A
E2li:>
/ )
Engine speed (rpm)lFU4l6EGR VALVE CONTROL VACUUM CHECK
NlQFVBBlCheck Condition
Engine coolant temperature:
85-95°C (185-205°F)
(1) Disconnect the vacuum hose from the throttle body EGR
vacuum nipple and connect a hand vacuum pump to the
nipple.(2) Start the engine and check to see that, after raising the
engine speed by racing the engine, vacuum raises pro-
portionately with the rise in engine speed.
NOTEIf there is a problem with the change in vacuum, it is
possible that the throttle body port may be clogged and
require cleaning.PURGE PORT VACUUM CHECK
Check Condition
N14FVBClEngine coolant temperature:
85-95°C (185-205°F)
(1) Disconnect the vacuum hose from the throttle body purge
hose nipple and connect a hand vacuum pump to the
nipple.
Engine speed (rpm)3FU262(2) Start the engine and check to see that, after raising the
engine speed by racing the engine, vacuum remains fairly
constant.
NOTE
If there is no vacuum created, it is possible that the throttlebody port may be clogged and require cleaning.

IL SYSTEM -MPI Svstem InsDection 4.8L Enaine>14-56FUE- _ ~-~~~~~ ~~ ~,~.
MPI SYSTEM INSPECTION <1.8L Engine>COMPONENTS
LncAT’n”’Ignition timing adjustment terminal
Fuel
ourno check terminal
Nl4PAAMAir-flow sensor
Intake air temperature sensor
Barometric pressuresensorCoolant temperature
sensornhibitor switch (A/T)
Inhibitor switch
-xT==-TL--==- IOlAO422
/Pxygen sensor

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>
outputDiagnosis code
referenceDiagnosis itemCheck item (Remedy)
orderOutput signal patternNo.Memory
7Engine coolantRetainedl Harness and connectortemperature sensor
:-rlrLn- 2’
l Engine coolant temper-
ature sensor
12A0107
8Crank angle sensor
:nn 22
Retainedl Harness and connector
(If harness and connector
are normal, replacedistributor assembly.)
12A0107
9No. 1 cylinder top
dead center sensorH
Lnn 23
Retainedl Harness and connector
(If harness and connector
are normal, replacedistributor assembly.)
12A0107
10Vehicle speed sensor24Retainedl Harness and connector
(reed switch)H
Lu 1 nnJln
l Vehicle speed sensor
(reed switch)
12A0107
11Barometric pressure25Retainedl Harness and connector
sensorH
u I nl-uvln
(If harness and connector
are normal, replace
Lbarometric pressure
12A0107sensor assembly.)
12Ignition timing adjust-36-l Harness and connectorment signalH
LUUI nluvuuL
12R0468
13Injector
:m 41
Retainedl Harness and connector0 Injector coil resistance
12A0105
14Fuel pump42Retainedl Harness and connectorH0 Control relay
LUUUI nn
12A0105
15EGR 43Retainedl Harness and connectorl EGR temperature sensor
H
u u u u-inn
l EGRvalvel EGR valve control sole-Lnoid valve
12A0105l EGR valve control vacuurr
16Normal state---H
Ln
12A0104
NOTEReplace the engine control unit if a malfunction code is output although the inspection reveals that there is no problem with the check
items.

14-62FUEL SYSTEM - MPI System Inspection <1.8L Engine>
INTAKE AIR TEMPERATURE SENSORNlmNABAir flow sensor
side connectorINSPECTION(1) Disconnect the air flow sensor connectors.
(2) Measure resistance between terminals
@ and @.
6FUO622
Temperature “C PF)Resistance kR
0 (32)6.0
20(68)2.780(176)
0.4(3) Measure resistance while heating the sensor using a hair
drier.
Temperature “C (“F)Resistance kfi
HigherSmaller(4) If the value deviates from the standard value or the
resistance remains unchanged, replace the air flow sensor
assembly.
ENGINE COOLANT TEMPERATURE SENSOR
NWQABE
INSPECTION(1) Remove engine coolant temperature sensor from the
intake manifold.
(2) With temperature sensing portion of engine
cool?nttemperature sensor immersed in hot water, check resist-
ance.16R1251
Temperature “C (“F)Resi’stance kQ
0 (32)5.920(68)
2.5
40 (104)2.7
80(176)0.3(3) If the resistance deviates from the standard value greatly,
replace the sensor.
INSTALLATION(1) Apply specified sealant to threaded portion and tighten to
specified torque.
Specified sealant: MOPAR Part No.4318034
or equivalent
Specified torque: 20
- 40 Nm (15 - 29 ftlbs.)(2) Fasten harness connectors securely.

14-64FUEL SYSTEM -MPI System Inspection <1.8L Engine>
Idle speed controlservo connector
6FU098t(3) Disconnect the idle speed control servo connector.
(4) Connect DC
6V between terminals @) and @ of the idle
speed control servo connector, and then measure the
resistance between terminals
@ and @ of the motor
position sensor connector when the idle speed control
servo is activated (caused to expand and contract).
Standard value: Smooth increase/decrease in accord-
ance with extension and retraction of
idle speed control servo plunger.
Caution
Apply only a 6V DC or lower voltage. Application of
higher voltage could cause locking of the servo gears.
(5) If there is a deviation from the standard value, or if the
change is not smooth, replace the idle speed control servo
assembly.
OXYGEN SENSORN14QDBAb
INSPECTIONCaution
1. Before checking, warm up the engine until engine
coolant temperature reaches 85 to
95°C (185 to 205°F).2. Use an accurate digital voltmeter.
(1) Disconnect the oxygen sensor connector and connect a
voltmeter to the oxygen sensor connector.
(2) While repeating engine racing, measure the oxygen sensor
output voltage.
EngineOxygen sensor
output voltageRemarks
Race0.6- 1 .OVMake air-fuel mixture
rich by accelerator
operation
NOTEFor removal and installation of the oxygen sensor, refer
toGROUP 11
- Exhaust Manifold.
Oxygen sensor installation torque:
40
-50 Nm (30 - 36 klbs.)
EGR TEMPERATURE SENSOR NIIRCHA~Refer to GROUP 25
- Exhaust Gas Recirculation System.
VEHICLE SPEED SENSORN14QEEBaRefer to GROUP 8
- Meters and Gauges.
AIR CONDITIONER SWITCHRefer to GROUP 8
- Column Switch.
N14QQABa