OBD Cylinder 9 Injection Timing Performance - Over Retarded
What it means
P01DB stands for Cylinder 9 Injection Timing Performance - Over Retarded. P01DB is a P code, so the fault sits in the engine, transmission and emissions systems. For P01DB, the second digit places it in fuel and air metering. For P01DB, work through the cause list below, cheapest checks first.
What to check first
For P01DB, clear the code, drive a short distance and read it again, since a code that comes back is still there and one that does not was history.
Check these first
- P01DB: Faulty or contaminated sensor in the fuel/air metering circuit
- P01DB: Damaged or shorted wiring or connector for the affected circuit
- P01DB: Vacuum leak or intake system restriction
- P01DB: Failing fuel pump, injector, or fuel pressure regulator
What to do next
P01DB reports from the fuel and air metering system. These steps cover P01DB in general, and the exact cause on your vehicle can differ from the cause named above.
- P01DB: Read freeze frame data and related codes with an OBD-II scanner
- P01DB: Inspect the affected sensor wiring and connector for damage
- P01DB: Compare live sensor readings (fuel trim, airflow, temperatures) to manufacturer specs
- P01DB: Smoke test the intake system if lean or vacuum conditions are suspected
- P01DB: Replace the failed component after confirming it with live data
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Updated
Generic SAE J2012 definition. Last updated 2026-08-30.