What is CID 81:
CID 81 refers to a problem with the fuel pump control circuit. The ECM detects that the fuel pump is not receiving the correct signals or is malfunctioning, leading to improper fuel delivery, misfires, or engine stalling.
Why This Happens:
- Faulty fuel pump control module.
- Shorted or damaged wiring in the control circuit.
- Loose or corroded connectors.
- Power supply issues affecting the fuel pump control module.
- ECM failure to interpret fuel pump data.
How to Fix It:
- Inspect the fuel pump control module and wiring for damage.
- Test the fuel pump to ensure proper operation.
- Check connectors for tightness and cleanliness.
- Replace the faulty control module if necessary.
- Inspect the fuel system for pressure inconsistencies or pump-related issues.
How to Avoid It Before It Happens:
- Regularly inspect the fuel system, including the fuel pump.
- Perform routine checks of the fuel pump control system.
- Keep connectors clean and free from corrosion.
- Perform diagnostic checks to monitor fuel system health.
- Clue’s fuel management services track fuel pump systems and prevent issues before they affect engine operation.
