NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [SKYACTIV-G 2.5T]


id0103q4812100

13

KNOCKING/PINGING-ACCELERATION/CRUISE

DESCRIPTION
•  Abnormal combustion occurs under the condition such as the temperature in the combustion chamber is too high resulting in abnormal noise.
•  Knocking sound occurs from the engine compartment during acceleration.
POSSIBLE CAUSE
•  Poor fuel quality
?  Fuel RON is not specified
?  Excessive cleaning agents added in fuel
•  Poor connection of KS, wiring harness
•  The following information for calculating ignition timing is incorrect:
?  KS signal
?  ECT sensor signal
?  IAT sensor No.2 (integrated in MAP sensor) signal
?  MAF sensor signal
•  Air suction in intake-air system
?  MAP sensor signal
?  Boost pressure sensor signal
?  Boost air temperature sensor signal
•  Combustion temperature is high
?  Cooling system malfunction
?  Carbon accumulation
?  Use of non-genuine spark plug
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.
?  Highly pressurized fuel may spray out if the fuel line is cut. Due to the following dangers occurring with a fuel spray, always complete the “Fuel Line Safety Procedure” to prevent the fuel from spraying. (See BEFORE SERVICE PRECAUTION [SKYACTIV-G 2.5T].)
•  Fuel may cause irritation if it comes in contact with skin and eyes.
•  If fuel ignites and causes a fire, it may lead to serious injury or death, and damage to property and facilities.
?  Fuel is highly flammable and dangerous. Fuel line spills and leakage can cause serious injury or death, and damage to equipment. Always refer to the “Quick Release Connector Removal/Installation (fuel system)” before performing the fuel hose installation, and execute the “Fuel Leakage Inspection” after installation. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T].) (See AFTER SERVICE PRECAUTION [SKYACTIV-G 2.5T].)
Caution
•  Disconnecting/connecting the quick release connector without cleaning it may possibly cause damage to the 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
VERIFY PCM DTC
•  Retrieve PCM DTCs using the M-MDS.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Go to the next step.
2
REPLACE FUEL
•  Drain the remaining fuel in the fuel tank and add the specified fuel.
•  Leave idling for approx. 15 min to refill the hose with fuel.
•  Does the symptom disappear?
Yes
Symptom troubleshooting completed.
(If customer has used fuel additive, give them advice not to use it)
No
Go to the next step.
3
VERIFY IF MALFUNCTION CAUSE IS OVERHEATING
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 ECT PID using the M-MDS.
•  Is the ECT PID value less than 116 °C {241 °F} during driving?
Yes
Go to the next step.
No
The cause of this concern could be from the cooling system overheating.
•  Perform the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.
4
VERIFY SPARK PLUG CONDITION
•  Remove all spark plugs.
•  Inspect the spark plug.
•  Is there any malfunction?
Yes
Replace the spark plug.
No
Go to the next step.
5
INSPECT INTAKE AIR SYSTEM FOR AIR SUCTION
•  Verify if there is air suction into the intake air system (such as between MAF sensor and intake valve, vacuum hose, evaporative hose, ventilation hose).
•  Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Go to the next step.
6
INSPECT MAP SENSOR
•  Access the following PIDs using the M-MDS:
?  MAP
?  BARO
•  Measure the intake manifold vacuum when idling (no load).
•  Does the difference between PIDs BARO and MAP nearly match the intake manifold vacuum value?
Yes
Go to the next step.
No
Replace the MAP sensor.
7
INSPECT BOOST PRESSURE SENSOR/BOOST AIR TEMPERATURE SENSOR
•  Inspect the boost pressure sensor/boost air temperature sensor
•  Is there any malfunction?
Yes
Replace the boost pressure sensor/boost air temperature sensor.
No
Go to the next step.
8
INSPECT MAF SENSOR
•  Inspect the MAF sensor.
•  Is there any malfunction?
Yes
Replace the MAF sensor/IAT sensor No.1.
No
Go to the next step.
9
INSPECT IAT SENSOR NO.2
•  Inspect the IAT sensor No.2 resistance.
•  Is there any malfunction?
Yes
Replace the MAP sensor/IAT sensor No.2.
No
Go to the next step.
10
INSPECT ECT SENSOR
•  Inspect the ECT sensor resistance.
•  Is there any malfunction?
Yes
Replace the ECT sensor.
No
Go to the next step.
11
INSPECT KS
•  Is there any malfunction?
Yes
Replace the KS, then go to the next step.
No
Remove the accumulated matter in the cylinder head using the following procedure:
•  Carbon remover
•  Overhauling
Go to the next step.
12
Verify the test results.
•  If normal, return to the diagnostic index to service any additional symptoms.
•  If a 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.