NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [ZJ, ZY]


id0103b0812100

13

KNOCKING/PINGING—ACCELERATION/CRUISE

DESCRIPTION
•  Sound is produced when air/fuel mixture is ignited by something other than 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
•  PCM malfunction
Warning
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:
•  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 the “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [ZJ, ZY].) (See AFTER SERVICE PRECAUTION [ZJ, ZY].)
Caution
•  If there is foreign material on the connecting area of the quick release connector, it might damage the connector or fuel pipe. To prevent this, disconnect the connector and clean the connecting area before connecting.

Diagnostic procedure

STEP

INSPECTION

ACTION

1
Perform the PID/DATA Monitor and Record Procedure and access the ECT PID.
Verify the 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
Go to the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.
2
Perform the PID/DATA Monitor and Record Procedure and access the following PIDs:
•  IAT
•  MAF
•  SPARKADV
Are the PIDs normal?
Yes
Go to the next step.
No
IAT PID is not specified:
•  Inspect the IAT sensor.
MAF PID is not specified:
•  Inspect the MAF sensor.
SPARKADV PID is not specified:
Repair or replace the malfunctioning part according to the inspection results.
3
Perform the KOEO and KOER self test.
Are any continuous memory DTCs present?
Yes
Go to the appropriate DTC inspection.
No
Go to the next step.
4
Inspect the engine compression.
Is there any malfunction?
Yes
Inspect for cause.
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
5
Install the fuel pressure gauge between the fuel pipe and the fuel distributor.
Start the engine and idle it.
Measure the fuel line pressure during idle.
Is the fuel line pressure correct during idle?
Yes
Inspect the ignition timing.
Repair or replace the malfunctioning part according to the inspection results.
No
Low:
•  Inspect the fuel line for clogging.
―  If normal:
•  Replace the fuel pump unit.
High:
•  Replace the fuel pump unit.
6
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 the 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.