No.8 Engine Runs Rough/Rolling Idle: Notes
ENGINE RUNS ROUGH/ROLLING IDLE - DESCRIPTION AND POSSIBLE CAUSE
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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.
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| POSSIBLE CAUSE |
- Air leakage from intake-air system parts
- A/C system improper operation
- Erratic signal to ignition coil
- Purge solenoid valve malfunction
- IAC valve improper operation
- EGR valve malfunction
- Erratic or no signal from CMP sensor
- Low engine compression
- Erratic signal from CKP sensor
- Poor fuel quality
- PCV valve malfunction
- Air cleaner restriction
- Restriction in exhaust system
- Disconnected electrical connectors
- Inadequate fuel pressure
- Fuel pump mechanical malfunction
- Fuel leakage from fuel injector
- Fuel injector clogging
- Engine overheating
- Vacuum leakage
WARNING:
- The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:
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