I can say I had to replace my PCM 2 months ago. It wouldnt shift into gear and would say transmission malfuntion, CEL too. So far So good. I dont know what yours could be it is odd did some research when I had mine replaced but your situation is a little different. Let us know what you find out I am curious.
Dave

 

PCM has been installed, truck runs badly. The throttle body was tested in a similar truck and works, now suspecting that the TPS and the new PCM are not communicating correctly. New throttle body on order.

 

I was just told by ford that the pcm for my 2000 F150 4x4 auto/AC has been discontinued? they found a used one a week away for $400 I told them to grab it! I called everywhere and had no luck finding one. And this way if there's a problem with it, its their problem. I'm just without a truck
Is this thred dead? I would like to know how it tuned out for you SpaceGhost?

 

Rock Auto sells remans in the $175 to $300 range.

 

Don't take this as gospel, but I have seen in a few posts in the past that a DFCM (Driver Fuel Control Module) (located over the spare tire) has destroyed a few PCMs in the past as in 'shorted them out'...something to check anyway...Good Luck !

 

That's what was wrong w/mine. Replaced 3 times before they figured that out. I'm just glad they did....

 

Question on PCM's. When a PCM goes bad does your truck stop, or will it still run, just not very well?

And where is the PCM located in a 2wd 1993 F 150 pickup, 4.9 6 cyl.?

Craig-

 

Speaking as an engineer, there is no excuse for this. All signals inputs and control outputs on a system-critical embedded controller like this should be able to handle a short or full voltage without failing.

 

The problem has been "solved".... at least so far. It was determined that the replacement throttle body was defective, and in turn took out the PCM ... again. After weeks of waiting, the truck is again on the road, and so far has been operating without a problem.

The shop assured me that all possibilities had been checked out, including the under dash connector. It seems to be getting better mileage, and overall running better than it has in some time.

I find it most frustrating that these parts are not stocked or readily available. The lame excuse from Ford that their suppliers had gone "bankrupt" and they were searching for new ones just shows the weakness of outsourcing parts.

Thanks for all the suggestions and ideas.

 

x2

I work for a major, though formally bankrupt, automotive supplier and I can say there is not a single automotive customer to whom we supply that does not require short to battery/short to ground testing for all inputs/outputs of our electrical devices. This has been true for at least a decade, and I suspect quite a bit longer. Of course, this does not mean strange things do not happen from time to time, but frankly this problem you are having is very unlikely.

Best of luck, hope the mechanics get you back on the road,
Mike

 

What is known is that your Powertrain Control Module failed. A new PCM also failed. Unless you (or the dealer) figure out what is causing the failures, then a third PCM could also fail.

Wiring issues can develop after installation. I don't know about your car in particular. But I have personally seen wires coming loose after years of use, exposure to the elements, et cetera. It's not a perfect world. Screws come loose all the time. What happens when one of those screws is holding down a ground wire? I've even seen wires that were chewed on by small animals. Don't ask me how, but little mice, squirrels, rats, and such can climb up into the underside of a car and chew on wires. It doesn't take much to cause electrical arcing.

 

Did anyone ever answer this gentlemans question?

The problem is with the COPs (Coil Over Plugs). Some Ford COPs have a problem with the epoxy sealant. Micro cracks develop (they cannot be see with naked eye) in the coils causing them to fail. The 1st sign of this is when the underside of the engine gets wet, creating steam that flows up into the engine compartment.

Sometimes only one COP may develop a short. When this happens it causes and OVER-CURRENT condition in the driver electronics of the PCM completely destroying the power section of the PCM. This in turn will (sometimes) cause all kinds of misleading and erroneous codes to appears.

The only solution is to replace all COPs (and the boots too, for extra insurance) to correct the recurrance of the problem. If you do not replace all of them you risk blowing your PCM again as you may have more than one COP failing.

Of course, if you replace all of the COPs and it still runs bad or not at all, you have blown another PCM and it will need to be replaced AGAIN.