This could be avery long post so i'll try to keep it brief.

My '94 E350 /460 / E4OD /RV just had its 3rd Distributor in 3 months replaced today and the mechanic says the computer/PCM is fried. Well 90% fried. The short question: Heard there is a place in NJ that rebuilds them. Is this a good move? (I live in the sticks in California).

Long part: It seems this all started with a torque convertor/solenoid pack replacement 6 months ago. We've been chasing why its been either slamming in and out of lockup or missing sporadically. Numerous parts have been replaced leading up to the distributor 3 months ago. All seemed to be fine then I took it in because the house generator quit working. While there the distributor quit.

SO: Did the PCM cause the other parts to fail or the other way around? If I put a new one in will it be subject to failure? Is the tail wagging the dog?

Advice?

Thanks-

 

I don't have extensive knowledge about your issues but I believe it might be possible to obtain a PCM from the better salvage yards, typically a lot less than new or a rebuilt one. LKQ Online is a great source if this is something you'd consider.

It would seem to me since your mechanic has already cited the PCM as problematic and it controls nearly every component or part you mention it would be my first thought it needs to be addressed before anything else.

In short time someone with more extensive knowledge should contribute---lots of smart guys here. You can also post this in one of the FTE forums that are more specific to your engine's model year and type. Your issues might not be specific to just your chassis.

Hope this is even slightly helpful!

 

Your PCM may be fried from old age, while most components are solid state they have capacitors that have an age limit. Some last decades and some don't.

But what you are describing here sounds like grounding. The computer connectors to the engine (I think they are black and white) have given me many problems in the past. Check here first, the pins may not be seating good, the female ends may have opened up. To fix you can open the male end a bit to get better contact.

 

You can buy a new / reman one here....ECM Depot | ECM Depot, Right Place Right Now or look in the Junkyards as suggested .....I would get new

 

Blageurt thanks. That looks like a good deal. Is there any reason at all why a new one would have issues?

I still am not comfortable with the components replaced during the TC job. Could they have caused this problem or is it the other way around?

 

I'm a Mechanical guy ...When it comes to electronic stuff I just replace it....I have no clue on what causes what to which...I just check wires / connections / grounds and continuity and then replace components....way less headache for me , plus PCM's and other stuff has come down ALOT in price the last few years....

 

Ford PCMs are cheap and fairly easy to find, but the common damage is a blown filtering capacitor on the 12v rail.

Anyone with basic soldering experience can replace those in no time. Even if you don't have a box of caps sitting around, you can order individuals from amazon for less than a dollar. Shouldn't cost more than 20 bucks to have an electronics repair shop do the soldering if you give them the caps.

Your van should be EEC-IV, and you should be able to use an OBD-I reader (like this http://www.amazon.com/Equus-3145-For.../dp/B000EW0KHW) to pull codes. If you have lots of codes relating to the transmission, EGR, etc, then you probably have the cooked capacitor issue.

 

So does anyone think the computer made the tranny malfunction or is it possible new trans parts made the ECU quit?

I do have a code reader and didn't have but a couple of codes. My ECU for some reason is harder to find. The designation is: F4TF-12A650-YA. It was sent out to a shop for diagnostics and declared DOA- not rebuildable. My concern is putting a new one in and having it self destruct. Is that realistic?

 

In my many years of working with electronics in industrial robotics some times electronics self destruct. Typically the capacitors and they sometimes do extensive damage when they do destruct. But most of the time electronic issues are caused due to external issues, like a short bad device/sensor.

If there is an issue with the external wiring or device that caused the ECU to fry, then yes it is reasonable to expect the replacement to fry as well.

Did you get a report back from the ECU doctors of what the issues were? If so please scan and post. Very few places do real electronic repairs and this may be the issue here.

Buy a ECU from a scrap yard that give warranties, plug it in and see what happens.

But before you do that post the codes you have as this may show a bad sensor.

 

Will your diagnosing shop say if they believe the issue to be contained within the ECU by itself or possibly caused by something external?

 

Before I turned it in for gennerator repair I had observed 2 codes; #1 cylinder misfire and OBD port not grounded (I think that's what it was- not 100% sure. I may have caused that when connecting and reconnecting the reader). When my new mechanic got around to reading the OBD he got no codes, but if he disconnected the batteries wouldn't he have erased them?

They want to charge me $240 for diagnosing the ECU. Their diagnosis is not rebuildable. All I've recieved is a photo of a fried ECU. They haven't told me what the fried part does. Wish I could post the pic but its one of 3 blue cylinders. The one in the lower right hand corner (sorry I'm not schooled in electronics).

He also want's to charge $940 labor for finding the problem on the RV, pulling and reinstalling the ECU and another $230 for another ECU.

Thing is it drove perfectly when I brought it there. Is it possible it got fried when he pulled the generator if he failed to disconnect the batteries?

thanks for the help.

 

Sounds like a never ending saga, one where you're almost completely at the mercy of those supposedly in the know about your issues.

I'm over my head in this and don't want to say or add anything misleading or in error. You might also post this in the Electrical Systems/Wiring Forums too: Electrical Systems/Wiring - Ford Truck Enthusiasts Forums

More than a few very smart guys there, perhaps with a bit more in-depth knowledge to share.

Best of luck--hope its nothing much more severe or costly!

 

Thanks JWA. Never ending saga is right. This all started back in October and $4000 ago. I think we've been dancing around not replacing the ECM and hopefully this will get me back on the road confidently again. I'll post on the other forum for feedback there.

 

These same sort of issues are potential problems for all of us who read anything here on FTE---I'm sure many of us share your aggravation and fear of rapidly depleted wallets with no clear end in sight.

Whatever you eventually please come update this thread----that would be helpful in the future I'm sure.

Best of luck!

 

Update:

I got my RV back yesterday. After much searching the mechanic found that the previous owner ran the positive run from his 3rd battery without a loom shielding it. It grounded against the shock mount.

After chasing this for 6 months I'm cautiously hopeful this is behind us. Someone please tell me its not only possible, its probable.

thanks to those who helped.
C-dad