Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine misfire
- Hard starting or extended cranking
- Poor fuel economy
- Black smoke from exhaust
- Engine stalling or hesitation under load
Most Likely Root Causes
- Faulty fuel injector driver circuit in ECM
- Damaged or corroded injector wiring harness
- Shorted or open injector circuit wiring
- Failed fuel injector
- Corroded or loose injector connector
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Component Location
Fuel injectors are mounted in the intake manifold or cylinder head depending on engine design, with wiring routed to the ECM.
Manufacturer Notes
P0200 is a general injector circuit code that typically sets when the ECM detects a fault affecting multiple injectors or the main driver circuit.
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