Mitsubishi 1989-1993 GALANT Service Manual page 31

ROUGH IDLE OR ENGINE STALL
Symptom
Rough idle or engine stalls
ENGINE HESITATES OR POOR ACCELERATION
Symptom
Engine hesrtates or poor
acceleration
ENGINE DIESELING
Symptom
Engine dieseling (runs after
ignition switch is turned off)
GENERAL - Master Troubleshooting
Probable cause
Vacuum leaks
Purge control valve hose
l
Vacuum hoses
l
Intake manifold
l
Intake manifold plenum
l
Throttle body
l
EGR valve
l
Ignition system problems
Idle mixture too lean or too rich
Fuel injection system problems
Exhaust gas recirculation (EGR) system
problems
Compression too low
Probable cause
Ignition system problem
Vacuum leaks
Vacuum hoses
l
Intake manifold
l
Intake manifold plenum
l
Throttle body
l
EGR valve
l
Air cleaner clogged
Fuel line clogged
Fuel injection system problem
Emission control system problem
EGR system always on
l
Engine overheats
Compression too low
Probable cause
TSB Revision
Reference page or remedy
17-3
16-32
Check idle speed control sys-
tem
13-8, 119, 205
17-22
14-5
Reference page
16-32
17-3
17-22
14-5
11-6