What does it mean?
P1213 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Cylinder 1 Fuel Injection Circuit Short to B+ .
Symptoms
- Check engine lamp on, and flashing once the misfire becomes severe
- Rough idle and a misfire clearly tied to cylinder 1
- Rich running, black smoke and a strong fuel smell if the injector is held open
- Fuel diluted engine oil and a wet, fouled plug on that cylinder
- Hard starting, stumbling and stalling at idle
Likely causes
- Insulation rubbed through where the injector wire runs alongside a permanent power feed
- Oil or water inside the injector connector bridging the supply pin to the control pin
- Internal short in the injector between the winding and its supply terminal
- Harness pinched under the valve cover, a cable clamp or a bracket
- Incorrect or damaged injector fitted that does not match the circuit
- Injector driver in the module already damaged by the short
How to fix it
- Read all codes first; several cylinders reported together point at a shared harness fault rather than one injector
- Unplug the injector and measure the control wire to ground with the ignition on; battery voltage there confirms the short
- Trace the harness from the module to the injector looking for melted or rubbed insulation near power feeds
- Inspect the connector for oil and corrosion, and check the injector winding against its own supply pin
- Measure injector resistance and compare it with the other cylinders
- Repair the harness and recheck the circuit before fitting a new injector
- Test the module driver last, only after the external short has been removed