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

id010397812100

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 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. (See BEFORE SERVICE PRECAUTION [LF, L5].) (See AFTER SERVICE PRECAUTION [LF, L5].)
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 using the M-MDS.
(See ON-BOARD DIAGNOSTIC TEST [LF, L5].)
Verify ECT PID is less than 116 °C {241 °F} during driving.
Is the ECT PID value 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 using the M-MDS.
Monitor each PID.
(See PCM INSPECTION [LF, L5].)
Are all PIDs normal?
Yes
Go to the next step.
No
IAT PID:
•  Inspect the IAT sensor.
MAF PID:
•  Inspect the MAF sensor.
Repair or replace the malfunctioning parts according to the inspection results.
3
Connect the M-MDS to the DLC-2.
Switch the ignition to ON (engine off).
Perform the DTC Reading Procedure.
(See ON-BOARD DIAGNOSTIC TEST [LF, L5].)
Are any DTCs present?
Yes
Go to the appropriate DTC inspection.
(See DTC TABLE [LF, L5].)
No
Go to the next step.
4
Is the engine compression correct?
(See COMPRESSION INSPECTION [LF, L5].)
Yes
Go to the next step.
No
Inspect for cause.
Repair or replace the malfunctioning parts according to the inspection results.
5
Inspect the fuel line pressure.
(See FUEL LINE PRESSURE INSPECTION [LF, L5].)
Is the fuel line pressure correct?
Yes
Inspect the ignition timing.
Repair or replace the malfunctioning parts according to the inspection results.
No
Low:
•  Inspect the following:
―  Fuel pump relay and fuel pump circuit
―  Fuel line for clogging
•  If there is no malfunction:
―  Replace the fuel pump unit.
High:
•  Replace the fuel pump unit.
6
Inspect the KS.
(See KNOCK SENSOR (KS) INSPECTION [LF, L5].)
Is there any malfunction?
Yes
Replace the KS.
(See KNOCK SENSOR (KS) REMOVAL/INSTALLATION [LF, L5].)
No
Inspect the ignition timing.
Repair or replace the malfunctioning parts according to the inspection results.
7
•  Verify the test results.
―  If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [LF, L5].)
―  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. (See PCM REMOVAL/INSTALLATION [LF, L5].)