Engine/Transmission (1998.5 - 2002) Won't start when warm. Scanner says its the ECM.

[Blacksdieselhp]

on a 2001 i put a new lift pump and an ez on. we drove it about 20 miles and went in to get lunch. When we came out and tried to crank the truck, It would not start. We put it on the scanner, and it says the ECM has a bad ground internally. Any of you guys seen this before. My first thought was injector pump timing. But I've never seen this code. The owner ended up cranking it with starting fluid and it ran fine. And if you let it sit for a couple of hours, it will crank right up. But when you cut it off, if it sits for more than 15-20 secounds, it won't crank. Fuel pressure is good and theres fuel at the injectors. Any help will be appreciated. Thanks

 

[NIsaacs]

If it was fine before the EZ, I would unplug it and try it again. Maybe bad EZ?





"NICK"

 

[Supermod56]

Yep, been known to happen, ECM failures are pretty rare on any modern cars.

Tom

 

[Blacksdieselhp]

I did take the ez off, but still the same. I scanned it with the ez off of course. But its really weird. After you crank it up and drive it, it will crank back fine within a few seconds, but if you let it set 15-20 seconds, it won't crank. Just like it is loosing prime. But its not.

 

[Blacksdieselhp]

By the way, this problem is on a 2001 3500 4wd auto.

 

[Gary - K7GLD]

You might try unplugging the ECM harness, and reseating the plug a few times to see if one or more contacts have become marginal in making proper contact, that frequently shows up in swings from hot to cold operation - I've seen that happen before on a car I had...

 

[Graphic man]

check all your grounds every where you can find one pull it off and clean,

bad grounds are common and its an easy and a cheep place to start

 

[Huff N Puff]

Graphic man is right start with all the grounds,including both battery posts the ECM cant differentiate,between internal and external grounds.

 

[Supermod56]

Can't say on the Cummins, but on all the gas motors I have worked on over the years, a bad ground is a common issue. Good place to start!!



Tom