Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine misfire on cold start
- Reduced engine power or hesitation during acceleration
- Poor fuel economy
- Engine may run on three cylinders or exhibit single-cylinder misfire
- Black smoke from exhaust under load
Most Likely Root Causes
- Faulty cylinder 1 fuel injector with internal short circuit
- Damaged or shorted injector wiring harness
- Corroded or damaged injector connector at cylinder 1
- Failed fuel injector driver circuit in engine control module
- Chafed wiring causing short to voltage in injector circuit
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Component Location
Cylinder 1 fuel injector is located at the first cylinder position in the engine firing order, mounted in the intake manifold or cylinder head.
Manufacturer Notes
Some manufacturers use high-impedance injectors that are more sensitive to wiring resistance and may set this code with marginal connector contact issues.
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