Common Symptoms
- Check engine light illuminated
- Rough idle or engine misfire on cylinder 5
- Poor acceleration or hesitation
- Increased fuel consumption
- Black or gray exhaust smoke
- Engine runs rough during cold start
Most Likely Root Causes
- Faulty fuel injector on cylinder 5
- Damaged or corroded injector wiring harness
- Poor electrical connection at injector connector
- Failed injector driver circuit in PCM
- Shorted injector coil winding
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Component Location
Cylinder 5 fuel injector is located on the fuel rail at the fifth cylinder position in the engine firing order.
Manufacturer Notes
Some vehicles may require injector flow testing or PCM reprogramming if multiple injector circuit codes are present simultaneously.
Also diagnosing J1939 SPN/FMI codes?
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