93 Explorer. CEL on with no codes.

[mayerrw]

1 have a 93 v6 4.0L explorer with 187K. The engine started running rough and the CEL came on but when try and use my KOEO code reader it indicates that the ECC is not responding.

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the EEC-IV section. Check the sticky threads on the top of this section for information on pulling & reading codes.