NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [MZR 1.5, MZR 1.6]

id0103e0812100

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 [MZR 1.5, MZR 1.6].) (See AFTER SERVICE PRECAUTION [MZR 1.5, MZR 1.6].)
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
Access the ECT PID using the M-MDS.
(See ON-BOARD DIAGNOSTIC TEST [MZR 1.5, MZR 1.6].)
Verify the ECT PID is less than 116 °C {241 °F}during driving.
Is the ECT PID value less than the specification?
(See PCM INSPECTION [MZR 1.5, MZR 1.6].)
Yes
Go to the next step.
No
Go to the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.
(See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [MZR 1.5, MZR 1.6].)
2
Access the following PIDs using the M-MDS:
(See ON-BOARD DIAGNOSTIC TEST [MZR 1.5, MZR 1.6].)
•  IAT
•  MAF
•  SPARKADV
Are all PIDs normal?
(See PCM INSPECTION [MZR 1.5, MZR 1.6].)
Yes
Go to the next step.
No
IAT:
•  Inspect the IAT sensor.
MAF:
•  Inspect the MAF sensor.
SPARKADV:
•  Inspect the CMP sensor and the KS.
Repair or replace the malfunctioning part according to the inspection results.
3
Connect the M-MDS to the DLC-2.
Perform the KOEO or KOER self test.
(See KOEO/KOER SELF TEST [MZR 1.5, MZR 1.6].)
Are any continuous memory DTCs present?
Yes
Go to the appropriate DTC inspection.
(See DTC TABLE [MZR 1.5, MZR 1.6].)
No
Go to the next step.
4
Inspect the engine compression.
(See COMPRESSION INSPECTION [MZR 1.5, MZR 1.6].)
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?
(See FUEL LINE PRESSURE INSPECTION [MZR 1.5, MZR 1.6].)
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 the test results.
•  If normal, return to diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [MZR 1.5, MZR 1.6].)
•  If malfunction remains, inspect related Service information perform repair or diagnosis.
―  If vehicle repaired, troubleshooting completed.
―  If vehicle not repaired or additional diagnostic information not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [MZR 1.5, MZR 1.6].)