NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [MZR 1.3, MZR 1.5]

id0103d7812100

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
•  Erratic signal to PCM
―  IAT sensor or related wiring harness malfunction
―  MAF sensor or related wiring harness malfunction
―  KS or related wiring harness malfunction
•  PCM DTC is stored
•  CMP signal malfunction
―  Loose installation CMP sensor and/or damaged pulse wheel
•  CKP signal malfunction
―  Loose installation CKP sensor and/or pulse wheel
•  Inadequate engine compression
•  Inadequate fuel pressure
―  Pressure regulator malfunction (built-into fuel pump unit)
―  Fuel pump mechanical malfunction
―  Fuel leakage from fuel system
•  Improper ignition timing
•  Poor fuel quality (i.e. Fuel RON is not specified, excessive cleaning agents added in fuel)
•  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 “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [MZR 1.3, MZR 1.5].) (See AFTER SERVICE PRECAUTION [MZR 1.3, MZR 1.5].)
Caution
•  Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to fuel pipe and 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
INSPECT COOLING SYSTEM FOR MALFUNCTION
•  Access the ECT PID using the M-MDS.
•  Verify the ECT PID value 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
Go to the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.
(See NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [MZR 1.3, MZR 1.5].)
2
VERIFY CURRENT INPUT SIGNAL STATUS
Caution
•  While performing this step, always operate the vehicle in a safe and lawful manner.
•  When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
•  Access the following PIDs using the M-MDS:
―  IAT
―  MAF
―  KNOCKR
•  Are all PIDs normal?
Yes
Go to the next step.
No
IAT PID is not as specified:
•  Inspect the IAT sensor.
MAF PID is not as specified:
•  Inspect the MAF sensor.
KNOCKR PID is not as specified:
•  Inspect the CMP sensor and KS.
Repair or replace the malfunctioning part according to the inspection results.
3
VERIFY PCM DTC
•  Perform the PCM DTC inspection using the M-MDS.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [MZR 1.3, MZR 1.5].)
No
Go to the next step.
4
INSPECT CMP SENSOR INSTALLATION
•  Inspect the CMP sensor installation.
•  Is the CMP sensor installed properly?
Yes
Go to the next step.
No
Install the CMP sensor properly.
(See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [MZR 1.3, MZR 1.5].)
5
INSPECT CKP SENSOR AND PULSE WHEEL
•  Inspect the CKP sensor and crankshaft pulley installation.
•  Are CKP sensor and crankshaft pulley installed properly?
Yes
Go to the next step.
No
Install the CKP sensor and/or crankshaft pulley properly.
(See CRANKSHAFT POSITION (CKP) SENSOR REMOVAL/INSTALLATION [MZR 1.3, MZR 1.5].)
6
INSPECT ENGINE COMPRESSION
•  Inspect the engine compression.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
7
INSPECT FUEL LINE PRESSURE
•  Install the fuel pressure gauge between fuel pipe and fuel distributor.
•  Start the engine and idle it.
•  Measure the fuel line pressure during idle.
•  Is there any malfunction?
Yes
Low:
•  Inspect the fuel line for restriction.
―  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
―  If there is no malfunction:
•  Replace the fuel pump unit. (pressure regulator or fuel pump mechanical malfunction)
High:
•  Replace the fuel pump unit. (pressure regulator malfunction)
No
Go to the next step.
8
INSPECT KS
•  Inspect the KS.
•  Is there any malfunction?
Yes
Replace the KS.
(See KNOCK SENSOR (KS) REMOVAL/INSTALLATION [MZR 1.3, MZR 1.5].)
No
Go to the next step.
9
INSPECT IGNITION TIMING
•  Inspect the ignition timing.
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Replace the fuel.
10
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.