Do I need a new PCM?

Hi all,

Been reading the forums and learning a lot for the last several months. Now I have a problem to post about - lucky me.

Sunday afternoon I was driving home from a job when my formerly problem free truck Died While Driving. The engine just quit. Both tanks about half full. After pulling over I cranked and cranked again, but not a sign of life from under the hood. Switched tanks and tried again. The tach moved during cranking so I ruled out the CPS. Next thought - fuel., so I walk home and get the spare fuel filter, replace the dirty filter then clean the FPR screen which looked totally blocked. Checked the filter bowl fuel level again after turning on the ignition, all seemed fine. Then I cranked again and got a few burps from the engine. After a few more times it started, but only ran a few seconds. I kept at it, but it would always die again though once it ran for over a minute.

I was ready for the Tow Truck. Had it towed to a nearby shop and went back this morning to try starting it again. It ran for 3 minutes then died. Checked in to the shop and waited for the call. It came late this afternoon, the guy said it was the computer. Looked like it had taken some water and needs replacement.

What do you guys think? Is that a reasonable diagnosis? If the PCM is still in the truck I might go back tomorrow morning and pull the Banks chip to see if that makes a difference.

What is a reasonable price for a new PCM? I looked at the DP-Tuner site, they have a programed new PCM for $250. Seems like that might be the way to go.

Your thoughts and advice are welcome.

Thanks

Hi BBT and welcome to SDD. Yes it sounds reasonable that the PCM could be damaged. It is hard to guess what your problem may be. Take the chip out and then see if it starts, if not a new PCM is next. Checkout your local Autozone for a replacement.

Dave

Definetly pull the chip, rule that out as a possiblity as being the culprit. Then move on to fuel pressure, see what you have for pressure. Get the codes pulled (CEL on?) Your IDM may be the problem as well. Where are you in California? We have several members out west and one may be near you.

Welcome to SDD, I hope we can give you some help here.

Try the CPS, the tach function is not a true test of a completely functioning CPS, if it doesn't work then the cps is culpret (most likely) if it does work then the CPS may or may not be good.

OK, some new info. Just got back from the mechanic. The PCM was pulled from the truck so I didn’t check it without the Banks chip. The guy said he would try it without the chip.

He said that a code for a bad PCM ROM keeps coming up after clearing. Did an injector test - all are working. The fuel pressure is OK. He is aware of the CPS and doesn’t think that is the problem.

I’m in San Rafael. Thanks for the replies, keep them coming.

Pull the chip is first thing.
Physical chip will omit the same issues as a CPS, and a dead PCM.
Good luck
Ron

Pulled the chip but the motor still dies as before. Jody has a PCM in stock for my truck which I’m going to have burned and shipped to arrive tomorrow.

Hopefully that will do it and I’ll be back on the road again by tomorrow afternoon.

Thanks