F250 wiring
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F250 wiring
I just bought an 84 F250. According to a ford dealer mechanic, a wiring harness in the engine bay was loose, and an exposed relay shorted against the metal firewall - lots of melted wires and a trashed relay. It blew fuses that control fuel pump. Mechanic replaced relay, but he found one wire left that he could not figure out where it went. Now, it runs fine, but when I turn off the ignition and pull key out, the engine keeps running. To kill the motor, I need to either 1) Pull the green relay apart or 2) touch unidentified exposed wire to ground. The Mechanic says I need to find a "loom" from another 1984 F250, like from a junker, and pull the identical wiring "loom" from the junker and splice it into my truck. Sounds reasonable - but cant I just look at another 1984 F250 and see where this unknown wire goes, then hook it up that way? I am figuring the unknown loose wire is somehow related to the engine continuing to run with ignition turned off. Any ideas? Anyone know where in Denver area I can look at a 1984 F250? Help.....
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F250 wiring
After you have shut it off.
Check the positive terminal on the coil to see if there is still power going to it.
You could have mentioned the colour code of the wire here and we could let you know from wiring diagram.
So post the code of the wire ok?
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
Check the positive terminal on the coil to see if there is still power going to it.
You could have mentioned the colour code of the wire here and we could let you know from wiring diagram.
So post the code of the wire ok?
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
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F250 wiring
>Sounds to me like it goes to the altenator. You could
>probably fix it by slicing a diode in the green line.
Forgive my ignorance - What is a diode? Are you talking about a green wire attached to alternator? Thanks.
>probably fix it by slicing a diode in the green line.
Forgive my ignorance - What is a diode? Are you talking about a green wire attached to alternator? Thanks.
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F250 wiring
>After you have shut it off.
>Check the positive terminal on the coil to see if there is
>still power going to it.
>
>You could have mentioned the colour code of the wire here
>and we could let you know from wiring diagram.
>
>So post the code of the wire ok?
>
> DENNIS - the loose wire has a black cover - but if it sparks when grounded its gotta be hot right? Sorry, I dont know squat about electrics.... Thanks.
>Dennis
>
>
>
>Please Don't Ask Me Any Tough Questions As:
>"I'm Saving My Memory For When I Develop Alzheimer's"
>
>
>78 F-150 429CJ,Silver
>w/Explorer Pkge.
>641/2-Mustang 260,Pre-World's Fair Car.
>64-Fairlane500 S/C waiting for a 390-4spd.
>68-Mustang 289-Sunlit Gold 80,892Mi
>78-Buick LeSabre 403 4V
>84 Volvo DL Wagon
>Check the positive terminal on the coil to see if there is
>still power going to it.
>
>You could have mentioned the colour code of the wire here
>and we could let you know from wiring diagram.
>
>So post the code of the wire ok?
>
> DENNIS - the loose wire has a black cover - but if it sparks when grounded its gotta be hot right? Sorry, I dont know squat about electrics.... Thanks.
>Dennis
>
>
>
>Please Don't Ask Me Any Tough Questions As:
>"I'm Saving My Memory For When I Develop Alzheimer's"
>
>
>78 F-150 429CJ,Silver
>w/Explorer Pkge.
>641/2-Mustang 260,Pre-World's Fair Car.
>64-Fairlane500 S/C waiting for a 390-4spd.
>68-Mustang 289-Sunlit Gold 80,892Mi
>78-Buick LeSabre 403 4V
>84 Volvo DL Wagon
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F250 wiring
[updated:LAST EDITED ON 06-Feb-02 AT 11:02 AM (EST)]Someone needs to put a test-light on the positve + terminal of the coil while someone else turns the ignition key off.
If there is still power to the coil wire,the engine will still run.
If this happens,there is probably a
powered wire (that Shouldn't be) attached to the coil
keeping the engine running.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
If there is still power to the coil wire,the engine will still run.
If this happens,there is probably a
powered wire (that Shouldn't be) attached to the coil
keeping the engine running.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
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F250 wiring
If I was gonna splice in a new loom - Does it need to be from a 1984 F250 or are other years/models equipped with same wiring? I have access to an 88 F150.... Thanks.
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Posting Guru
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From: Durham
F250 wiring
Will the truck start with your black wire on ground? Will it continue running with the ignition in the on position and the black wire connected to ground? Does the black wire get hot if connected to ground in either of the above situations?
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F250 wiring
[updated:LAST EDITED ON 06-Feb-02 AT 03:16 PM (EST)]>If I was gonna splice in a new loom - Does it need to be
>from a 1984 F250 or are other years/models equipped with
>same wiring? I have access to an 88 F150.... Thanks.
The 84-86 for sure !
88 is under the other guide line > 87-92
It's worth a look to see if it would though.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
>from a 1984 F250 or are other years/models equipped with
>same wiring? I have access to an 88 F150.... Thanks.
The 84-86 for sure !
88 is under the other guide line > 87-92
It's worth a look to see if it would though.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
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Posts: 8
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F250 wiring
OK - I put a light on the mystery black wire. It is hot with engine and ignition on, it is hot with ignition off and engine running, it is cold when engine and ignition are off. On the coil - If the coil is the item mounted to the right interior of engine bay, just behind battery, and attached to battery + positive terminal, then: terminal on coil that attaches to battery with large red cable is always hot. There is an orange wire off the ?coil? that has a fuse in it - this is hot with engine and ignition on, ignition off and engine running, and it goes cold when the ignition and engine are off. any thoughts? Have I accurately identfied the coil? Thanks!
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F250 wiring
[updated:LAST EDITED ON 07-Feb-02 AT 11:44 AM (EST)]NO !
The coil is the item that is attached to the distributor by the spark plug type wire in the center of it.
On it is a - (neg terminal) and a +(pos Terminal)
The + terminal is the one you need to test for power with the key off.
and engine running.
You're somewhere around the Voltage regulator and starter solenoid.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
The coil is the item that is attached to the distributor by the spark plug type wire in the center of it.
On it is a - (neg terminal) and a +(pos Terminal)
The + terminal is the one you need to test for power with the key off.
and engine running.
You're somewhere around the Voltage regulator and starter solenoid.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
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F250 wiring
I have discovered this problem only exists when I have the fuel tank switch selcted to the rear tank - when the front tank is selected, the car starts, runs and shuts off as it should.... I can run with the rear tank, but if it is selected when you turn off ignition, engine still runs.
Posting Guru
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From: Durham
F250 wiring
I think you have your black wire, which should be a ground, melted somewhere to your rear tank fuel pump. The power continues to feed somehow back thru your altenator to keep the truck running...I hate finding wiring problems!!! I would guess that if you are on the front tank that you do not get any power thru the black wire.
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