OK, went to tow a car today, truck fired up and I got about a mile away when it accelerated on it's own, then died and every time I try to start it now it revs to 3000 RPMs and then drops rpm then stalls. It also blows black smoke when this happens. I stepped on the throttle and it made no difference. I haven't moved the PMD yet to the front bumper and when I felt it, it was barely warm to the touch. I scanned it and got codes 22 and 15 but they don't make much sense to me. I really feel lost without a truck! Please help!

DTC 15 - Engine Coolant Temperature (ECT) Sensor Circuit High (Low Temp)

DTC 22 - Accelerator Pedal Position 1 Circuit Low

 

The ECT code could be valid-checking with a scan tool that shows what the ECT reading that the ECM sees would be helpfull as well as the APP readings.

With a 94 if you intend to do a lot of DIY and keep the truck for some time an investment in the pro version of GMTD ScanTech would be wise.

It is a laptop based scan tool with the ability to give the information you need now along with bi-directional control of some systems.

The codes need to be investigated,but you have the symptoms of a failing flight systems PMD.

Or a bad IP.

The cheapest route to take is buy a PMD relocation kit with new PMD and resistor /heatsink and extension harness and get that installed,it is not a waste of money because every electronic IP owner should have a spare PMD.

If that solves the problem great.

 

OK, which kit do I need and from who do I get it from? What do you suggest?

 

The lowest price with the best warranty.

Amazon has a dorman PMD and an available kit that is as good as you are likely to get,be sure to get a new resistor as well#5,#7 are good choices.

 

A new PMD did the trick! The truck not only fired right up, it runs very smooth and NO more codes at all. I really think the old PMD was failing since I got the truck. It was always slow to start, the idle had dropped, it would die once in a blue moon at idle and the check engine light was always going on and off while driving which would shut off the cruise which was annoying.


I must say that "dorman" relocation kit is a POS. The screws were allen and made so crappy a metric or SAE allen wrench wouldn't fit. The holes on the heat sink aren't tapped very good making the screws go in pretty hard. The retainer snapped off the PMD side of the harness when I plugged it in. The PMD itself was surprisingly "Made in the USA"