well, this has perplexed me and my ford dealership for a couple weeks now. the cel on my 05 gt has been coming on and off for no reason. i bring it into the dealership and they say they cant tell why its coming on, they had ford corporate on the phone the other day about it, and they might be putting a bulletin out about it...anyone else having this problem?? no codes, just a cel...

 

I am having a similar problem with my 06. The CEL will come on randomly and when I plug in my Predator to check the codes, it says there are none. I have been hesitating taking it to the dealer since I have a few mods. If anyone else knows what would cause this please let me know. I did have a "check fuel cap" warning the first time it happened. I cleared the codes using the Predator and now all I get is the CEL, no "fuel cap" warning.

 

So I decided to take it in to the dealer for the problem above. Turns out my I had a fauly gas cap. Dealer replaced it under warranty and I have no further issues. I still don't know why the Predator wouldn't show the P0455 code the the dealers tool picked up right away.

 

Man, it could be one of the many computer "signal inputs" or "control outputs" causing this issue. Could be a loose termination at any of those points. Trying to find an intermittent problem is very difficult.

One way to find the culprit is to datalog the OBDll while driving. I would think that the dealer could hook you up with a datalogger for a while.

If they wont then you may have to purchase your own datalogging software and ..........yeah........a laptop to run it. The laptop will need a USB port.

Man, I hate intermittent problems in Direct Digital Control Systems.