191 Fuel system at lean adaptive limit (front)
How to read it
Code 191 reads as 1 flash, pause, 9 flashes, pause, 1 flash 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 191 mean?
191. Fuel system at lean adaptive limit (front). This code sets when your vehicle computer detects fuel system at lean adaptive limit (front).
Common causes of 191
- Vacuum or intake leak
- Low fuel pressure or a clogged fuel filter
- Faulty fuel system
- Open or shorted wiring or a bad connector in the circuit
- Dirty or weak fuel injectors
How to fix 191
- Confirm the code and read the flash sequence again
- Check for vacuum and intake leaks
- Inspect the fuel system and its connector for damage and corrosion
- Measure fuel pressure and check the fuel filter
- Replace the fuel system or a failed part only after the tests