MPI –
Troubleshooting
13-29
INSPECTION PROCEDURE 12
When the engine is hot, it stalls at idling. (Die out)
Probable cause
In such cases as the above, the cause is probably that ignition system, air/fuel mixture,
idle speed control (ISC) or compression pressure is defective.
In addition, if the engine suddenly stalls, the cause may also be a defective connector
contact.
D
Malfunction of the ignition system
D
Malfunction of air-fuel ratio control system
D
Malfunction of the ISC servo system
D
Drawing air into intake system
D
Improper connector contact
D
Backflow of secondary air to the intake system
Were the battery terminals disconnected recently?
Yes
After warming-up, let the engine run at idling for about 10 minutes.
No
MUT-
II
Diagnosis code
Are diagnosis codes displayed?
Yes
Refer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Check the ISC servo for operation sound.
NG
Check the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
Check the injector for operation sound.
NG
Check the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
OK
Does the engine stall right after the accelerator pedal is released?
Yes
Clean the throttle valve
area.
Adjust the fixed SAS.
(Refer to P.13-30.)*
No
Does the engine stall easily again?
No
While carrying out an intermittent malfunction simulation test (Refer
to GROUP 00 – Points to Note for Intermittent Malfunctions.), check
for sudden changes in the signals shown below.
D
Crank angle sensor signal
D
Injector drive signal
D
Fuel pump drive signal
D
Air flow sensor signal
D
Secondary ignition signal
D
Engine-ECU power supply
voltage
Yes
MUT-
II
: Engine stalling inspection when the engine is warm and
idling. (Refer to P.13-50, INSPECTION PROCEDURE 42.)
OK
Check the ignition timing.
(Refer to GROUP 11 – ENGINE ADJUSTMENTS.)*
NG
Check that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
D
Check the ignition coil, spark plugs, spark plug cables.
D
Check the secondary air supply system. (Ensure that there is no backflow of secondary air into the intake system.)
D
Check if the injectors are clogged.
D
Check the compression pressure.
D
Check if foreign materials (water, alcohol, etc.) got into fuel.
NOTE
*:
Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).