13 Engine RPM below the self test lower limit or idle speed motor did not move
How to read it
Code 13 reads as 1 flash, pause, 3 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 13 mean?
13. Engine RPM below the self test lower limit or idle speed motor did not move. This code sets when your vehicle computer detects engine rpm below the self test lower limit or idle speed motor did not move.
Common causes of 13
- Idle speed set too low or engine stalling during the test
- Idle speed control motor stuck or not moving
- Vacuum leak or intake restriction lowering idle
- Throttle plate or linkage binding
- Base idle not set correctly
How to fix 13
- Repeat the test with the engine at normal operating temperature
- Check base idle speed and adjustment
- Inspect the idle speed control motor for movement and carbon
- Check the throttle body and linkage for binding
- Retest once idle speed holds within range