NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [L8, LF, L5]

id010346812100

13

KNOCKING/PINGING - ACCELERATION/CRUISE
DESCRIPTION
Sound is heard when the air/fuel mixture is ignited by something other than a spark plug (such as hot spot in combustion chamber).
POSSIBLE CAUSE
•  Engine overheating due to cooling system malfunction
•  ECT sensor malfunction
•  IAT sensor malfunction
•  MAF sensor malfunction
•  KS malfunction
•  Erratic signal from CMP sensor
•  Inadequate engine compression
•  Inadequate fuel pressure
Warning
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system:
•  Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.
•  Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual.
Caution
•  Disconnecting/connecting the quick release connector without cleaning it may cause damage to the fuel pipe and the quick release connector. Always clean the quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

Diagnostic procedure

STEP

INSPECTION

RESULTS

ACTION
1
Connect the M-MDS to the DLC-2.
Access the ECT PID.
Verify ECT PID is less than 116°C {241°F} during driving.
Is the ECT PID less than the specification?
Yes
Go to the next step.
No
Inspect the cooling system for the cause of the overheating.
2
Connect the M-MDS to the DLC-2.
Access the IAT and MAF PIDs.
Monitor each PID.
(See PCM INSPECTION [L8, LF, L5].)
Are the PIDs normal?
Yes
Go to the next step.
No
IAT PID: Inspect IAT sensor
MAF PID: Inspect MAF sensor
3
Connect the M-MDS to the DLC-2.
Switch the ignition to ON (Engine off).
Are there any DTCs displayed?
Yes
DTC is displayed:
Go to the appropriate DTC inspection.
(See DTC TABLE [L8, LF, L5].)
No
No DTC is displayed:
Go to the next step.
4
Is the engine compression correct?
(See COMPRESSION INSPECTION [L8, LF, L5].)
Yes
Go to the next step.
No
Inspect for cause.
5
Inspect the fuel line pressure.
(See FUEL LINE PRESSURE INSPECTION [L8, LF, L5].)
Is the fuel line pressure correct?
Yes
Inspect the ignition timing.
(See ENGINE TUNE-UP [L8, LF, L5].)
No
Low:
Inspect the fuel pump relay and fuel pump circuit.
Inspect the fuel line for clogging.
If there is no malfunction, replace the fuel pump unit.
High:
Replace the fuel pump unit.
(See FUEL PUMP UNIT REMOVAL/INSTALLATION [L8, LF, L5].)
6
Inspect the KS.
(See KNOCK SENSOR (KS) INSPECTION [L8, LF, L5].)
Is the knock sensor normal?
Yes
Inspect ignition timing.
No
Replace the KS.
(See KNOCK SENSOR (KS) REMOVAL/INSTALLATION [L8, LF, L5].)
7
•  Verify test results.
―  If normal, return to the diagnostic index to service any additional symptoms.
―  If the malfunction remains, inspect the related Service Information and perform repair or diagnosis.
•  If the vehicle is repaired, troubleshooting is completed.
•  If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM.