Isuzu 2000 Trooper Workshop Manual page 719

6A–6 ENGINE MECHANICAL
Rough Engine Idling or Engine Stalling
Condition
Trouble in fuel injection system
Trouble in emission control system
Others
Possible cause
Throttle shutting off incomplete
Throttle position sensor circuit open
or shorted
Fuel injector circuits open or shorted
Fuel injectors damaged
Fuel pump relay defective
Mass Airflow Sensor circuit open or
poor connections
Mass Airflow Sensor defective
Manifold Absolute Pressure Sensor
circuit open or poor connections
Manifold Absolute Pressure Sensor
defective
Engine Coolant Temperature Sensor
circuit open or poor connections
Engine Coolant Temperature Sensor
defective
Intake Air Temperature sensor circuit
open or poor connections
Intake Air Temperature
defective
Ion sensing module cable broken or
poor connections
Ion sensing module defective
Vehicle Speed Sensor circuit open or
shorted
Vehicle Speed Sensor defective
Powertrain Control Module defective
Exhaust Gas Recirculation Valve
circuit open or poor connections
Exhaust Gas Recirculation Valve
faulty
Canister purge valve circuit open or
poor connections
Canister purge valve defective
Evaporative Emission
Purge control valve defective
Trouble in ignition system
Engine lacks compression
Valve incorrectly seated
Air Cleaner Filter clogged
Valve timing incorrect
Idle air control valve broken
Fast idle solenoid defective
Positive Crankcase Ventilation valve
defective or clogged
Correction
Correct or replace
Correct or replace
Correct or replace
Replace
Replace
Correct or replace
Replace
Correct or replace
Replace
Correct or replace
Replace
Correct or replace
sensor Replace
Correct or replace
Replace
Correct or replace
Replace
Replace
Correct or replace
Replace
Correct or replace
Replace
Canister Replace
Refer to "Hard Start"
Refer to "Hard Start"
Lap valve
Replace filter element
Readjust
Replace
Replace
Replace