I've been trouble shooting this one for a while now. Everything runs perfect until after about 10 minutes. Then its like you've shorted out the key and the van shuts off. When you first turn the key on the check engine always comes on for a short period...normal. However after the van dies nothing will work and the check engine light no longer comes on when you turn the key. I have to wait for a long time for it to come on again. If that check engine light doesn't come on then nothing is going to run. I've checked the fuel pump relay, replaced the fuel pump, fuses are all good. I can't find a short anywhere. I guess my question is: When you first turn the key on isn't it the computer that makes the check engine light come on for that brief 30 seconds, tells the fuel pump relay to kick on, runs the EGR Valve for a sec? When I am having my problem non of these things happen when I turn the key on. I've looked around and have been told to check the ASD Relay. I don't know which one it is but after pulling two relays apart and seeing there wasn't anything wrong with them...I'm doubting the relay theory. I'm exhausted so any help would be appreciated. I'm going to run the van tomorrow again until it dies and see if anything comes up on the computer codes. The last thing I can think of.

 

The power to the Engine computer is being cut off.

Eliminate the Grounds as culprits. Clean the battery terminals. Remove and clean the battery to engine ground, battery to firewall ground, and the engine to frame ground. The engine to frame ground might not even exist. Add one.

You cannot have too many grounds, and 80% of all electrical issues are caused by bad grounds, and that is a conservative number.

The PCm could also be at fault

 

The starter never has an issue turning over so I don't see a ground issue. Cleaned cables and checked all the power at the fuses under the hood...that all looks good. The van will crank until the battery goes dead so there's not a ground issue. Only when the check engine light comes on when you turn the key will it start...and it will run just perfect. I haven't dug into the computer yet. Looks like its in a well protected black case under the hood but I'm not sure. If I could imagine a situation it would be the power going to the computer was flakey and causing the whole van to malfunction. When it goes off the check engine light flashes and you can hear the relays clicking. Like a UFO just flew over. Haven't checked codes though...tommorow. But I don't think it actually throws codes when this happens because I took it to a garage once before and they couldn't reproduce the problem...gave it back to me...and it did it on the way home.

 

I will check all of those grounds and add a new one tomorrow...sorry I misread your post.

 

It sounds like a bad PCM to me. As it heats up it fails to operate.

 

Kills me to just let the party van sit and collect dust. I think I've got this down to the Engine Control Module just being broken. I took it off the engine wall and checked the wiring harness for any bad connections or broken wires and nothing. I did notice that when I squeeze the ECM it will kill the van and then it will reproduce the clicking of the relays and short circuit/bad connection symptoms of flashing (not engine code blinking). Anyway I'm ready to drop a couple hundred bucks on a new unit but I'd like some advice on where I should order this. Advanced gave me $277 quote and I thought that was pretty steep. Any suggestions would be appreciated. Looking to order new ECM today.

 

I got a reman ECM from Cardone through Rockauto.

Unfortunately, they had the parts numbers for the manual and automatic transmissions mixed up, which I discovered only after taking apart my old ecm and noticed the numbers matched with the manual transmission model.

Rockauto never thought I was worth being re imbursed for shipping charges, but I now stick it back to them by looking up a 5% discount code every time I order something.