What causes Ford code 558?

Hose damaged Wiring EGR solenoid ECM

How do I fix Ford code 558?

Check the vacuum hoses for damage, a blockage or a wrong connection Check the circuit wiring and harness for damage, chafing or a poor splice Test the EGR solenoid and replace it only if it fails its own test Test the ECM last, only after every circuit test has passed Clear the code, then retest to confirm the fix holds

558 EGR vacuum regulator circuit failure

Q: What does Ford code 558 mean?

Ford code 558. EGR vacuum regulator circuit failure. Applies to 1981-1995 Ford, Lincoln and Mercury EEC-IV vehicles.

Make: Ford (1981-1995)
Category: Powertrain - Auxiliary Emissions Controls
Severity: Check Engine Light
Applies to: 1981-1995 Ford, Lincoln and Mercury EEC-IV vehicles

How to read it

Code 558 reads as 5 flashes, pause, 5 flashes, pause, 8 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 558 mean?

558. EGR vacuum regulator circuit failure. This code sets when your vehicle computer detects egr vacuum regulator circuit failure.

Common causes of 558

Hose damaged
Wiring
EGR solenoid
ECM

How to fix 558

Check the vacuum hoses for damage, a blockage or a wrong connection
Check the circuit wiring and harness for damage, chafing or a poor splice
Test the EGR solenoid and replace it only if it fails its own test
Test the ECM last, only after every circuit test has passed
Clear the code, then retest to confirm the fix holds