First off, this forum is really SWEET. Moderators have posted factory service manuals (FSM's) on here that are just invaluable. Here is a little example of that.

My 95 Dakota V6 3.9 2WD auto with 87M orig miles, repeatedly blew an IAC code. Replaced the IAC with an Autozone, then an AdvanceAuto, then an O'Reily, then a NAPA and finally a MOPAR OEM $100 from the stealer. All based on GOOD advice from here.

Still kept blowing the IAC code time after time after resets - and then eventually constantly. This was causing periodic rough starting and stalling.

So I checked for shorts/grounds/continuity in the wiring from the IAC back to the PCM plug. All checked out OK.

Should have paid more attention to the "code 053" that showed up on occasion - PCM communication failure. Only showed up once in a great while.

Then I found this section in the FSM and tried it out: https://www.box.com/s/184517d078f9a9475b5d
Uploaded and named it: How I found out my PCM was whacked - NOT the IAC motor
Check it out.

BINGO - when doing voltage testing on the four IAC lines coming from the PCM while running, two of them went up to full battery voltage ~ 13.5 volts.

If you follow the troubleshooting chart, NONE of these reads should have exceeded 5.0 volts; and if they do exceed 5V, the solution is to "REPLACE THE PCM."

Just ordered a $250 Cardone reman online. This better do the trick or I'm jumping off the nearest bridge

Thanks for all the feedback. Will post results in a week or so. Hope this helps others.

Dave H. Appleton, WI Sunday 8/19/2012 3pm central

d c horan at earth link dot net

 

Thanks for sharing that info. Good luck . . . Hope it works out for you.

 

Let us know Follow the manual instead of throwing parts at it who'd a thought... I make that mistake all the time Think I know it all These new systems are too complicated for the old school approach lucky my buddy tony has more patience than I do

 

Same thing happened to mine. The IAC controller circuits went bad on the pcm. I finally figured it out one day when I would unplug the IAC and no CEL would light and no code would be thrown even though it should because that simulates an open in the IAC circuit. Bought a new pcm and fixed my issues.

 

Hey post up a link to that site where you got the reman unit! would be good to have in the parts link in the faq!

 

Kinda funny - since I was recently bashing AZ parts for poor quality

But this is a Cardone reman and I had $50 off and a $30 coupon and $20 reward zone credit - net net $150 for a reman versus $100 for a junkyard one with 187,000 miles - a no brainer.

http://www.autozone.com/autozone/par...ntifier=887480

Dave H. Appleton

 

Opened up the ORIGINAL PCM that came out of my truck.
Kinda ugly. Like a 1" layer of cracked "rubber jello" and dust covering everything.

Wonder if the heat under the hood finally took its toll on the unit/components.

It was 100F+ and I was driving stop and go all around town the day the crap started happening.

Can't wait to put the reman unit in and see if I have a new vehicle that runs like it has only 87,000 miles on it

Any special procedures after installing a new PCM beside letting it idle for awhile???

Thanks.

Dave H. Appleton, WI

 

I have a spare 95 V6, A/T computer here collecting dust; a Mopar reman (of which were rumored to have been done by cardone at one time go figure)
I got it off a parts truck just in case the one on my 94 crapped out. so far my 94 is good.

 

So I get the new AutoZone/Cardone PCM from FedEx tonight.

Anxiously do the PCM swap.

Now I get a MIL code 27 - injector control circuit #6. And of course that cylinder's injector is not firing and there is a serious engine miss. DANG IT.

So I put the old PCM back in and get the typical bad IAC circuit, but no code 027. Cylinder/injector 6 is firing fine.

So I put the "new" PCM back in and guess what - code 027 again.

Put the old PCM back in, no code 027.

Lug my pissed off a$$ to AZ - they won't refund me but did order me another one.

Any bets if that next one is going to be "DOA" too so to speak???

American quality at its finest.

For some reason, I am beginning to think this could be a prolonged affair until a "good one" ends up in my hands.

Dave H. Appleton, WI

 

V,

PM me with a confirmation of the part number (4886660???) and your asking price. I am still stuck with the AZ one

Or email me at dchoran@earthlink.net

I am Paypal verified at dchoran@athenet.net Ebay ID dchoran74x4 100% rating for 10+ years

Thanks Dave H.


1995 Dodge Trucks Dakota

Application Data: 3.9 Liters and w/A.T.; w/OEM #4856068, 4886660, 56028339
Units are pre-programmed at the factory.