37 Fuel system indicates rich at idle
How to read it
Code 37 reads as 3 flashes, pause, 7 flashes on the check-engine light. Jumper the self-test input to signal return at the test connector, then run the key on engine off self test and the running self test, counting the check-engine flashes each time.
New to flash codes? The OBD-I code reading guide walks through the paperclip method, code 12, and reading two-digit codes.
What does Ford code 37 mean?
37. Fuel system indicates rich at idle. This code sets when your vehicle computer detects fuel system indicates rich at idle.
Common causes of 37
- Fuel pressure too high
- Leaking or stuck fuel injectors
- Faulty oxygen sensor
- Rich purge from the evaporative system
- Mass air flow measurement high
How to fix 37
- Confirm the code and measure fuel pressure
- Inspect the oxygen sensor signal for a true rich reading
- Test the injectors for leakage or a stuck open condition
- Check the evaporative purge for a rich condition
- Repair or replace a failed part only after the tests