Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine misfire on cylinder 7
- Reduced engine power or hesitation during acceleration
- Increased fuel consumption
- Engine may run on seven cylinders instead of eight
Most Likely Root Causes
- Faulty fuel injector on cylinder 7
- Damaged or corroded wiring harness to cylinder 7 injector
- Poor electrical connection at injector connector
- Failed injector driver circuit in powertrain control module
- Shorted injector circuit wiring
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Component Location
Cylinder 7 fuel injector is located on the engine block or cylinder head corresponding to the seventh cylinder in the firing order.
Manufacturer Notes
Some V8 engines may require specific relearn procedures after injector replacement to ensure proper fuel delivery calibration.
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