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First Major Failure??? PCM crapped out

548
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Ok gang. Here's the scoop:

Driving back to work yesterday. 1468 miles on the Boss. Check engine light comes on. Dropped off right away at dealer. Dealer has to call Ford. Today: PCM is faulty - will take 2-3 days to get Boss specific PCM in at dealer. Bottom line: no Boss until next week.

Will update then. At least it's under warranty.

:-[
 
548
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PCM came in yesterday. They're still working on it today. Must be some new/tricky setup necessary with the Boss PCM or PCMs in general. Still no Boss to drive...4 work days and counting....
 
jimprw said:
PCM came in yesterday. They're still working on it today. Must be some new/tricky setup necessary with the Boss PCM or PCMs in general. Still no Boss to drive...4 work days and counting....
Weird. I would think it would be plug and play. Worst case scenario just reflashing it after hooking it up which doesn't take long. I hope there's not an electrical issue like a bad wiring harness or something.
 
cloud9 said:
jimprw said:
PCM came in yesterday. They're still working on it today. Must be some new/tricky setup necessary with the Boss PCM or PCMs in general. Still no Boss to drive...4 work days and counting....
Weird. I would think it would be plug and play. Worst case scenario just reflashing it after hooking it up which doesn't take long. I hope there's not an electrical issue like a bad wiring harness or something.

That does seem strange, try to ask about the details if you can.
 
548
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Just got my car back. Seems to run just fine. After talking to the service mgr, best I can say is I guess we really don't know what triggered the check engine light in the first place. From what he told me, when the tech started working on it they had to call Ford Tech line to analyze whatever problem it was. Ford basically said to reflash the PCM - whether to see if the PCM was faulty or to see if the check engine light would come on again, I'm not sure.

But as it went, when they were uploading the PCM with the data, the process stopped mid-load and when they tried to reload a second time, key data was unable to be recovered. An additional call to Ford apparently indicated that at that point reloading the PCM was futile and Ford recommended they put in a whole new PCM and flash it from the ground up.

So that is where things stand. Car runs great now. I guess I'll have to wait to see if the issue returns or if the original PCM actually was faulty. In any case, I have my car back. Yea! :D
 
Seems like any interruption during a reflash means bad things. Always have a fully charged battery and sometimes worth even hooking up to a charger, although I never have. I had a bad Pro-Cal tuner from FRPP that caused my PCM to go into fail safe. Had to have it towed to the dealer to get it unlocked, but didn't require a new PCM. Glad you're back on the road Jim!
 
548
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Thanks, Gary. Hopefully my issue was an anomaly. But if anyone else runs into any PCM issues, please post!
 
1,255
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GA
cloud9 said:
Seems like any interruption during a reflash means bad things. Always have a fully charged battery and sometimes worth even hooking up to a charger, although I never have. I had a bad Pro-Cal tuner from FRPP that caused my PCM to go into fail safe. Had to have it towed to the dealer to get it unlocked, but didn't require a new PCM. Glad you're back on the road Jim!

Just like any electronic part, you get a bad one every now and then. You just got lucky. ;) Flash memory devices can sometimes have intermittent errors, but if it won't successfully re-flash at all then it is defective for sure.
 
Well you have to wonder if there is bad software written into these. I have seen a couple of people that say the CEL came on or they experienced limp mode and the dealer was unable to pull any codes. Now this had problems recovering data, sounds like this may be an issue.
 
548
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Sorry to report that a week later and just under 100 miles since picking up the car with the new(and newly flashed) PCM, the CEL has come on again and car is back at dealer. They pulled a whole bunch of codes this time all apparently related to camshaft timing errors. I didn't notice the car went into limp mode when the light came on, nor was there any noticeable change in how the car was running. Fortunately, I was on my way home from work yesterday when it happened and drove right into the local dealership service area as the dealer is right on my way home.

I expect I'll be waiting again. Since I haven't heard anyone else having this issue, I'm assuming I'm just lucky. And since there is probably very little precedent for any such issue (besides me) with the specific Boss calibrations, I'm a bit worried that this may be a drawn out affair. Anyway, I'll update here so there is some standing record in case anyone else sees issues among our group. :mad:
 
Wow bummer Jim. When they called the Hotline, had there been any other reports of this specific issue? First I've heard of it. Hope you're back on the road soon.
 
548
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Thanks, Guys.

Today's update: no component parts failure from testing. Now they're checking the wiring harness for shorts etc. If it is a bad wiring harness somewhere, I guess that would be the good news if the entirety can be replaced and that fixes the problem. If this is going to be one of those drawn out phantom electrical issues that never seem to get resolved, then Ford will get their car back. Needless to say this isn't what I signed up for. But for now will continue to look at the glass being half-full.

As far as whether or not Ford has had any similar issues besides with mine, I don't know. I'll be sure to ask the tech for more detail when I check on it again.
 
I hope you get this worked out soon. It's definitely no fun to buy a limited edition car like these and have issues like this. Takes the fun out of owning the car and leave a bad taste in your mouth.

Good luck to you!!
 
548
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Got the Boss back last Friday. Diagnosis was that there was a short in the wiring harness going from the battery out to the various termination points in the engine compartment. The issue apparently was a short where the harness first splits. (not sure why they didn't pick that up the first time it went into the shop)

Put a couple of hundred miles on it over the weekend and all runs very well at this point. Gave it a pretty good workout too - up to about 120mph and backing off, and it purred. Also quite noticeable was the fact that the slight burp I noticed (on a different thread) when accelerating between 4K and 4200K RPMs is gone. So, I suspect the wiring issue must have been the culprit there too.

Since the wiring harness was a single component, I'm not worried about phantom undiagnosed electrical problems down the road at this point. Right now all is good and I have my toy back. Ford customer service on the whole issue was very responsive. Area rep also contacted me by phone to tell me the issue was resolved. Nice touch.

Right now I'm smiling! :)
 
332
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I may have the record for the earliest Boss 302 component failiure. Car had less than 500 miles on it and while driving on Route 15 in PA I ran into a heavy rain storm. About 5 minutes after I hit the rain, the airbag light comes on. It stayed on for 2 days until I got it back to the dealer. They had to order a new airbag control unit (or whatever) and kept the car for 2 days. No other problems since then...now have about 1950 miles on the odo.
 
548
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Yep - you might hold on to that record. Good to hear it was a minor problem. Keep the information coming gang - helps everyone out to stay on top of this stuff in (fairly) real time.
 

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