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Discussion Starter #1
im redoing all the wiring in my car for the computer since it keeps popping the relay...anyone done this or know a good place to get the computer wiring harness?
 

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Discussion Starter #4
you dont think its the actual wiring? what could it be im so stumped im down to pay someone like 500$ for labor to fix it
 

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you dont think its the actual wiring? what could it be im so stumped im down to pay someone like 500$ for labor to fix it
mani dont even have a clue it could be almost anything let me look around and talk to some people and wheres tengram when you need him?
 

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Discussion Starter #6
i appreciate it jordan you have no idea how much i want to just give up...also now its not idling when cold (efi) what could that be? probably many things
 

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why do you guys reffer to haynes?

Chiltons is wayy better

and if your popping relays theres def. a short somewhere
 

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why do you guys reffer to haynes?

Chiltons is wayy better

and if your popping relays theres def. a short somewhere
I think that he was talking about actually getting the harness--not where to look up the wiring. If that's the case then I'd say look at Painless Wiring for a harness. If you're looking at getting the diagram and troubleshooting yourself then I'd say get on Ebay and find the Ford manual for your year.
 

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Ummm, most relays are rated at like 30 AMPS! You should blow the fuse before you blow the relay. Check for a bad ground or ?? did you redo the wiring?
 

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if you are going to change the harness u have to take the center console and dash board while your at it u may as well change the heater core.. i did mine it about 5 hours total of labor u can get a wireing harness from ebay or a junkyard.

what problems are you having with your car?
 

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Discussion Starter #13
ok so here it is, the relay for my computer blew once, and i put a new one in and then i drove it for 5 days then it blew again, now the new one is working fine...but now my car is not idling when i first start it in the day and it pops like its back firing...
 

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Discussion Starter #16
tmoss, im not sure how could i check or maybe you could tell me what would go wrong with my car if the circuits were bad...
 

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the coil circuit closes the relay contact to let power through. You can use a multimeter on the coil to see how much resistance is there - measure posts marked #85 and #86. The power circuit can fail if too much current is drawn through it - it overheats the metal causing the spring to anneal and you loose contact pressure. Too much current also causes the contact faces to pit from arcing when they close and open - this reuslts in too much resistance and "voltage drop" across the contacts. A good way to test for this is to turn the pump on and measure with a voltmeter on a low scale on the relay power connections - numbers 30 and 87. If you have more than .5v "dropped" across the contacts then they are failing.

Once you determine which circuit is bad, you look at what might be casuing the problem. Eithe way it is probably too much current being drawn. If it's the pump side, the fuel pump may be going bad.

Anothe rthing to check is the relay contacts in the relay socket - if they are not making good contact, they can overheat and cause connection problems and voltage drop too.
 

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Discussion Starter #18
the coil circuit i measure that on the posts on the actual coil? and where do i check the power circuit...on the back of the fuel pump relay??
 
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