So I've been having lots of issues with the truck lately, and it hasn't thrown a code. So naturally, I verified the check engine lightbulb is not burned out. On the OBD2 port there is voltage,

But get this, because I dont trust that stupid light... I started unplugging and playing. Here's what I have found:

Disconnected cam sensor: runs and drives exactly the same, no check engine light
Disconnected MAF: barely runs, still no code

Disconnected various coils: barely runs, still no code

Is there anything I can do to make it throw a code? How do I go about troubleshooting something like this? All the repair material I've read is dependant upon codes, and well, without them I can't do too much

 

So after doing some research, it turns out on GM vehicles the CEL can be deactivated and certain categories of codes/ all codes can be ignored if that is how the tuner set them up.

Does anyone know if this can be done on a Ford, or if anyone has had experience doing it?

I checked the pinout of my OBD2 (with the Fluke) port and everything is live and working, but for some reason the PCM isn't acknowledging anything that should throw a code~ I'm wondering if perhaps the dealer that sold me the truck deactivated the CEL... it turns out everything else they told me about the truck was a lie.

On the plus side, in the search for my PCM I found receipts behind the glovebox, turns out the truck spent at least a year or two in Miami Gardens.

 

I have found that it takes two faults of the same problem in two different run cycles. So to get your code to show, make the problem then shut it off and restart. code should come up.