Mitsubishi Eclipse 1990 Service Manual page 448

Scan tool 119
Code General scan tool
No. 71
51
[Comment]
Background
The PCM monitors the fuel system for compliance with emission standards.
Range of Check
Engine coolant temperature is greater than
Closed loop operation
Set Condition
The test fails if the fuel control system increases pulse width by 25% long term memory
and 12% short term compensation due to a lean condition.
SCAN TOOL SENSOR READ TESTS (Data list)
05 Engine coolant temperature sensor (Refer to
SCAN TOOL SENSOR READ
27 Intake air temperature sensor
SCAN TOOL SENSOR READ
11 MAP sensor reading (Refer to
63 Oxygen sensor volts (rear) (Refer to
Transaxle: gear
SCAN TOOL SENSOR READ TESTS (Data list)
02 Oxygen sensor volts (front) (Refer to
during sudden racing
OK:
SCAN TOOL SENSOR READ TESTS (Data list)
02 Oxygen sensor volts (front) (Refer to
OK: Repeat and
idling.
Check the fuel pressure. (Refer to
OK
Check the following items.
Check the injectors for operation sound.
Clean the injectors.
Check the positive crankcase ventilation system.
Check the fuel pump.
Check the fuel filter and fuel line for blockages.
Check for exhaust gas leaks.
Check for contamination (water, kerosene, etc.) in the fuel.
ENGINE (NON-TURBO)>
Fuel System Lean
NG
to
I
NG
range
NG
alternately when
TSB Revision
Troubleshooting
Probable
Engine coolant temperature sensor
Intake air temperature sensor failed-
Head gasket
Exhaust manifold cracked
Injectors failed
MAP sensor failed
Heated oxygen sensor failed
Fuel pressure regulator
Fuel filter or fuel line blocked
Fuel pump failed (insufficient discharge)
Incorrect fuel used
PCM failed
Check the engine coolant temperature circuit.
(Refer to INSPECTION PROCEDURE 38.)
Check the intake air temperature circuit.
(Refer to
Check the MAP sensor circuit.
(Refer
Check the heated oxygen sensor (front) circuit.
(Refer to INSPECTION PROCEDURE 42.)
__
PROCEDURE 39.)
,