I'm helping to troubleshoot a friend's FD and we have a new puzzle: the car trips a CEL and when I check for codes I get a solid CEL. No blinking to count of any kind.

What on earth might be going on? Nothing about that one in the FSM that I could find.

The CEL system was working earlier because we found and fixed a Purge control and OMP code.

 

Do you have another ECU to try? Some internal ECU issue causing the CEL and/or it's not completely re-setting for whatever reason?

 

Just a WAG (I really don't know what I'm talking about here... ), but is there by any chance a relay involved with the CEL? And could it be sticking on?

Dave

 

If you get a solid CEL when checking for codes, something is wrong. The light should come on for a second then go out.

Make sure you're jumpering TEN and GND, and that your jumper wire is making a good electrical contact.

Dale

 

I agree, I think that there is an internal ECU problem. The engine light comes on by the ECU grounding it, or at least a lot of other cars do it like that.

So you either have a short to ground in the CEL light circuit, or an internal ECU error.

So the CEL is always on constantly, never blinks or nothing?

 

I suppose it's good that it's a suspected ECU problem.

I'm confident the jumpering is good as it was repeated several times. Every time, the CEL would come on and stay on in the <on> position.

The plan was to install a spare ECU of mine to see if that had any effect. It wasn't available yesterday.

Jim, we did get the OMP changed. That is not fun - it took me underneath with a flex-head socket on an extension plus another person in front with their hand wedged under the OMP just to loosen the back lower OMP bolt.

 

^^oh yes, changin the omp is definetly a good time!

 

Good to hear. Yeah, it's not something I want to do again anytime soon. If you have some suggestions for that 'how-to' thread, feel free.

On a related note to your possible ECU issue...
For various reasons I'm suspicious that it was my stock ECU that was cooking the OMP sensor. Did it on two OMPs. Both times it kicked the CEL (and subsequent limp mode) during high RPM and WOT. Continuity and resistance tests were always normal/within spec. No issues since the PFC though.