No. 8 Engine Runs Rough/Rolling Idle: Notes

WARNING: This page is about a different variant/trim than selected.

SYMPTOM CHART (ENGINE RUNS ROUGH/ROLLING IDLE)

8	ENGINE RUNS ROUGH/ROLLING IDLE
DESCRIPTION	Engine speed fluctuates between specified idle speed and lower speed and engine shakes excessively. Idle speed is too slow and engine shakes excessively.
POSSIBLE CAUSE	Idle learning of drive-by-wire control system is not completed. Electrical connector disconnection External fuel shut off or accessory Poor fuel quality Fuse malfunction Ignition wiring malfunction Air leakage from intake air system Vacuum leakage PCM ground circuit (1E, 1F, 1G, 1BE, or 1BF) malfunction Improper installation of EGR valve PCM DTC is stored. Engine overheating MAF sensor and related wiring harness malfunction Erratic signal from PSP switch Improper operation of A/C system CKP sensor and teeth of crankshaft pulley malfunction Ignition system malfunction Ignition coil and related wiring harness malfunction Spark plug malfunction Improper operation of drive-by-wire control system Excessive or insufficient fuel pressure Fuel pump relay or fuel pump circuit malfunction Restriction in fuel line Pressure regulator malfunction (built-into fuel pump unit) Fuel pump malfunction Fuel leakage from fuel system Fuel injector malfunction Purge solenoid valve malfunction EVAP control system malfunction Exhaust system part malfunction CMP sensor and teeth of camshaft malfunction EGR valve malfunction Improper operation of variable valve timing control system Low engine compression PCV valve malfunction Improper valve timing 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 .) (See AFTER SERVICE PRECAUTION .) CAUTION: Disconnecting/connecting the quick release connector without cleaning it may possibly 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.

ENGINE RUNS ROUGH/ROLLING IDLE

DESCRIPTION

Engine speed fluctuates between specified idle speed and lower speed and engine shakes excessively.
Idle speed is too slow and engine shakes excessively.

POSSIBLE CAUSE

Idle learning of drive-by-wire control system is not completed.
Electrical connector disconnection
External fuel shut off or accessory
Poor fuel quality
Fuse malfunction
Ignition wiring malfunction
Air leakage from intake air system
Vacuum leakage
PCM ground circuit (1E, 1F, 1G, 1BE, or 1BF) malfunction
Improper installation of EGR valve
PCM DTC is stored.
Engine overheating
MAF sensor and related wiring harness malfunction
Erratic signal from PSP switch
Improper operation of A/C system
CKP sensor and teeth of crankshaft pulley malfunction
Ignition system malfunction
- Ignition coil and related wiring harness malfunction
- Spark plug malfunction
Improper operation of drive-by-wire control system
Excessive or insufficient fuel pressure
- Fuel pump relay or fuel pump circuit malfunction
- Restriction in fuel line
- Pressure regulator malfunction (built-into fuel pump unit)
- Fuel pump malfunction
Fuel leakage from fuel system
Fuel injector malfunction
Purge solenoid valve malfunction
EVAP control system malfunction
Exhaust system part malfunction
CMP sensor and teeth of camshaft malfunction
EGR valve malfunction
Improper operation of variable valve timing control system
Low engine compression
PCV valve malfunction
Improper valve timing

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 .) (See AFTER SERVICE PRECAUTION .)

CAUTION:

Disconnecting/connecting the quick release connector without cleaning it may possibly 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.