86 bronco
Lead Driver
Joined: Sep 2002
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From: Gateway to the West
Constant open IAC or an issue with the circuit that controls it. Have you pulled codes to see if you are getting any IAC-related fault codes? Make certain you have no open vacuum barbs on the throttle body itself. If the IAC is dirty, the valve can stick open. You can clean it with throttle body cleaner that is safe for catalytic converters and coated throttle bodies. Make certain to keep any liquid out of the electronic end of the IAC.
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Lead Driver
Joined: Sep 2002
Posts: 9,182
Likes: 12
From: Gateway to the West
Kem,
Jog my memory, why would it be necessary to run the 86 harness? What changed between 86 and 90 that necessitates this? Just curious. I do understand keeping the harness and PCM matched but I want to understand what the differences are that make it necessary.
Jog my memory, why would it be necessary to run the 86 harness? What changed between 86 and 90 that necessitates this? Just curious. I do understand keeping the harness and PCM matched but I want to understand what the differences are that make it necessary.
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Hotshot
Joined: Jul 2002
Posts: 14,285
Likes: 12
From: Bend,OR
the efi harness for 85-86 where wired differently. they changed in 87 so the pinouts would be different and certain things wont be talking.
www.fordfuelinjection.com.
you need to either run the 90 harness and 90 ecu or get an 85-86 harness to work with your current ecu.
www.fordfuelinjection.com.
you need to either run the 90 harness and 90 ecu or get an 85-86 harness to work with your current ecu.
Hotshot
Joined: Jul 2002
Posts: 14,285
Likes: 12
From: Bend,OR
so i dont understand what you changed then. because the sensors are all in the same places on either motor. so in other words you should be able to take any efi 5.0 from 85-91 and drop it in and connect up your 86 harness and run your 86 ecu with no problems.
can you tell us what exactly you changed on your harness?
can you tell us what exactly you changed on your harness?