Multi-code OBD2 diagnosis

Enter all the codes your scanner showed, not just the first one. We give you the overall severity, whether you can keep driving, the order in which to check them and how they relate to each other.

Summary

Overall severity
Medium
Can I keep driving?
Yes, but with caution
Estimated cost
$20 to $450
Codes analyzed
1 of 1

The order below is the recommended one: first the codes that can cause the others. After each repair, clear the codes and check which ones come back.

Order of inspection

  1. P1131 HO2S11 Lack of Switching, Sensor Indicates Lean (Ford, Bank 1) Medium

    On Ford, Lincoln and Mercury, the P1131 code means the bank 1 front oxygen sensor (HO2S11) is stuck reading lean and not switching. Expect a rough idle or surging. Most of the time the mixture really is lean.

    Step-by-step diagnosis for P1131