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NOT a Ford problem....

Printed From: Unofficial Allis
Category: Other Topics
Forum Name: Shops, Barns, Varmints, and Trucks
Forum Description: anything you want to talk about except politics
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=169879
Printed Date: 06 Sep 2025 at 11:33am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com


Topic: NOT a Ford problem....
Posted By: jaybmiller
Subject: NOT a Ford problem....
Date Posted: 07 Apr 2020 at 8:20am
Ok, so neighbour starts his GMC pickup from storing over winter....starts easy, runs good, warms up,blablabla.... turns key off, key in hand, truck is STILL running !! Disconnects battery... STILL running !!!!
So.. anyone know WHY ?? I do.....


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3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water



Replies:
Posted By: steve(ill)
Date Posted: 07 Apr 2020 at 8:23am
must be running off the alternator ?  Something shorted or STUCK in wire circuit ?

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Like them all, but love the "B"s.


Posted By: chaskaduo
Date Posted: 07 Apr 2020 at 11:23am
Didn't they use a diode or idiot light for that problem on old GM's?

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1938 B, 79 Dynamark 11/36 6spd, 95 Weed-Eater 16hp, 2010 Bolens 14hp


Posted By: jaybmiller
Date Posted: 07 Apr 2020 at 3:58pm
2011 GMC...
yeah Alternator must have a diode shorted , so it's powering the engine.
If, IF, it'd be a stick shift stopping would have been a lot easier....
got another donor truck today, one with that idiotic engine in it that burns more oil than gas..will swap alternators....


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3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water


Posted By: Brian Jasper co. Ia
Date Posted: 09 Apr 2020 at 12:44am
Probably stuck contacts in the ignition switch. Ignition switches were not unusual on that style truck. It's nothing for the alternator to power everything at idle. The thing to do would be check for power moding DTCs in the body control and ECM.

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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford


Posted By: Tbone95
Date Posted: 09 Apr 2020 at 6:54am
Originally posted by Brian Jasper co. Ia Brian Jasper co. Ia wrote:

Probably stuck contacts in the ignition switch. Ignition switches were not unusual on that style truck. It's nothing for the alternator to power everything at idle. The thing to do would be check for power moding DTCs in the body control and ECM.
But, "Disconnected battery and still running".  ?


Posted By: fixer1958
Date Posted: 09 Apr 2020 at 7:28am
Seems it would have a substantial battery drain if either were the case.
Any aftermarket stuff on it?


Posted By: BuckSkin
Date Posted: 09 Apr 2020 at 1:15pm
You didn't specify whether it was gasoline or diesel.
It is common on diesels with an electrical shut-off to have the tip get worn on the little rubber shut-off plunger and run with the battery dis-connected.


Posted By: jaybmiller
Date Posted: 09 Apr 2020 at 2:43pm
run of the mill ,basic  gas ( 4.? or 5.??) engine, no aftermarket stuff.
 start it up, yank off battery , take key out... still runs. disconnect big alt wire...it dies...

now I'm wondering about the key, since it's fuel injected/ electric fuel pump...just how does anFI engine run without power to injectors ????? hmmmm, sounds more like the switch....

will have to wait as the 'machine' dumped some wet white here this morning..... and I'm onto other projects...


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3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water


Posted By: BuckSkin
Date Posted: 09 Apr 2020 at 4:35pm
Years ago, the wife had a Chevrolet Corsica (not a wise choice of transportation even when new); one night, she came in and announced "my car won't turn off".
I went out and, sure enough, it would not shut off.
It being an automatic (another poor choice), I began scratching my head as to how to kill the engine; then, I happened to remember that, if you came to a stop with the A/C running, it would die.
I flipped on the A/C and the engine immediately died.
The problem on that one was a key-switch gone bad.


Posted By: fixer1958
Date Posted: 10 Apr 2020 at 5:37am
Might have a relay staying energized with the key off. Some have key off power. Have to be grounded to work.
Something has to keep the PCM alive if it still runs.
If it does it again pull a relay in the fuse box under the hood on the left front.
Should be marked on the lid. PWR/TRN something like that.




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