CEL + Rough Ride - Can't Read Codes

[dirkhamstra]

I recently purchased a 2005=6 Jeep LJ 4.0 6 speed 152k miles. Until yesterday is ran great but the annoying CEL is on and truck engine idles and rides rough. This happened overnight - no changes made by humans. On top of that the OBD readers at AutoZone and two other car part stores are unable to read any codes. Two questions: what could be the potential cause of the CEL and the engine running rough 2. how to fic the IBD reading?

Thanks!
-dirk

 

[JKP]

You can get the codes on the odometer by turning the key on off on off on quickly and don't start it.

If this doesn't work, your PCM may be on the way out.

 

[dirkhamstra]

You can get the codes on the odometer by turning the key on off on off on quickly and don't start it.

If this doesn't work, your PCM may be on the way out.

Thanks @JKP - I forgot to mention that I tried that method - got nothing, the whole set of tests is run but now code(s)

 

[JKP]

Disconnect the battery for several minutes to reset the PCM.

 

[tr21triton]

have you changed the spark plugs ?

 

[AndyG]

I recently purchased a 2005=6 Jeep LJ 4.0 6 speed 152k miles. Until yesterday is ran great but the annoying CEL is on and truck engine idles and rides rough. This happened overnight - no changes made by humans. On top of that the OBD readers at AutoZone and two other car part stores are unable to read any codes. Two questions: what could be the potential cause of the CEL and the engine running rough 2. how to fic the IBD reading?

Thanks!
-dirk

There’s a company in Florida called wranglerfix.

@Wranglerfix owns it

Talk to him if you can and also look into your catalytic converter’s ...

I think if you’ll talk to Mark down there you’ll really be glad you did