VIN 2 LBZ fuel issue

BD_F

FHRITP
Apr 12, 2015
7
0
0
Sin City
40° at night, cold start, truck starts fine, ran it for 30 seconds to back it into my driveway. Next morning, 40°, start the truck, truck is running like it has a heavy cam in it. Loping at idle, but my injector balances won't display at all. No CELs. Figured it was a closed injector, but it never got better. Seems low on power, engine shakes the whole truck at idle. Engine note is completely different at WOT. FRP stays constant with what the Desired is. Swapped the fuel filter and added additive and it made barely any difference. Help?

Update:
Took it to the stealership, they said the ECM is having problems communicating with the fuel system. It's "intermittent" where it'll sense it and drop it, hence why it won't throw a code. Also said my BCM chassis ground connector is showing high resistance, but I cleaned that with no luck.

Where and what wires should I look for, for the "fuel system?" They want to try a new ECM and see if that fixes it...
 

menifee

New member
Jan 6, 2018
9
0
1
40° at night, cold start, truck starts fine, ran it for 30 seconds to back it into my driveway. Next morning, 40°, start the truck, truck is running like it has a heavy cam in it. Loping at idle, but my injector balances won't display at all. No CELs. Figured it was a closed injector, but it never got better. Seems low on power, engine shakes the whole truck at idle. Engine note is completely different at WOT. FRP stays constant with what the Desired is. Swapped the fuel filter and added additive and it made barely any difference. Help?

Update:
Took it to the stealership, they said the ECM is having problems communicating with the fuel system. It's "intermittent" where it'll sense it and drop it, hence why it won't throw a code. Also said my BCM chassis ground connector is showing high resistance, but I cleaned that with no luck.

Where and what wires should I look for, for the "fuel system?" They want to try a new ECM and see if that fixes it...
Do you have a 5th wheel y plug installed?

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menifee

New member
Jan 6, 2018
9
0
1
Negative. It had a good neck, but it was pulled before I bought it. And the block has nothing installed under the dash.
Reason why i ask is because the y plug in the rear of the truck that connects to factory tow plug harness for 5th wheels goose neck etc those plugs corrode out causing low voltage low ground to pcm . Just a heads up.. i had similar problems this was the problem!

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menifee

New member
Jan 6, 2018
9
0
1
Reason why i ask is because the y plug in the rear of the truck that connects to factory tow plug harness for 5th wheels goose neck etc those plugs corrode out causing low voltage low ground to pcm . Just a heads up.. i had similar problems this was the problem!

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This connection!
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BD_F

FHRITP
Apr 12, 2015
7
0
0
Sin City
I havent had time to get out and do it honestly...
However, I got ahold of some Head GM Tech at a dealership,
also has a Dmax, he doesnt think its an PCM issue.
He says its a possible issue at 2 or 7 but would have to see it for himself.
Its been a week and now he wont respond to me.
Any luck??

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