First time turning the key: Fuel pump won't prime/run

Also, incase I missed it. Are you sure you have the right 02 harness? They are different between the years. It might do the fuel pump issue but it makes the car run like crap.
 
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How many connectors do you have on the driver side shock tower that connect the dash harness to the computer harness? You could have one or two plugs. Also, you might want to look into the horn issue first. You might have a wire that is grounded. Also, there is a difference in the dash harness between the 4cyl. and V8 harness. Been there done that. As most have said about the relay under the seat, it's not that somone has messed with it. It's the fact that the 4cyl. cars went with the FP relay in the ccrm and not under the seat. That does not mean the wiring/connector for the FP relay is not there. You need to verify that. Also, when you look under the seat don't confuse the connector for power lumbar with the relay connector.

On the driver side shock tower i only have 1 plug and its brown.

I think perhaps the horn could be an issue with someone telling me they gave me a 1991 harness when in all actuality i have different year headlight harness. I have not found any diagrams for the horn circuit.

I am almost positive i have NO relay under the seat. tonight when i get home im pulling the seat out to check under the carpet. I did have the CCRM on the passenger side shock tower that was part of the 4cyl computer harness. It was discarded with the 4cyl computer harness and now i have a 1991 v8 computer harness. If there was no relay under the seat and it was on the computer harness wouldn't that mean i would need a computer harness from a 92-93 V8 inorder to have that fuel pump relay under the hood?
 
As you've seen, since you removed the I4 harness, you need to find the FP relay pigtail from your donor harness or create/splice together a pigtail for the FP relay.

I honestly would have no idea where to even start to do something like this..

i'm really bummed, i thought this was going to be plug and play like most all other 4-8 swaps i've seen.
 
Yes im sure about this - the 02 harness plugged right into the 91 v8 harness


Not saying that you have the wrong one, but just because it plugged in to the harness in no way means it is the correct harness. Ford changed wiring pin locations between the years and used the same connector.
 
91 IIRC was a stand alone year. there were changes made that year and that year only. 92-93 were different and using a 92-93 harness would only make things more difficult. there has to be something that we are missing here.

is there a spare pig tail that you can put into the plug underneath the driver seat? put a bolt in it if you have to and turn the ignition to see if the FP primes.
 
You may still want to check under the seat because that's where most fuel pump relays were on 92's is what I've heard because I am looking to do the conversion and have done a ton of research. Only the later 92's had the relay on the shock tower by the other. The wiring might be under the seat and the 4 cylinder might just not use it, so the relay isn't there but the wiring could be. It would just suck to pull out the whole harness to then find out that the wiring is under the seat.
 
nah, if he's running a 91 harness I am amazed he even got it to start at all.

90, if you cant find a harness send me a pm. I gotz one I was saving for a project.
 
You may still want to check under the seat because that's where most fuel pump relays were on 92's is what I've heard because I am looking to do the conversion and have done a ton of research. Only the later 92's had the relay on the shock tower by the other. The wiring might be under the seat and the 4 cylinder might just not use it, so the relay isn't there but the wiring could be. It would just suck to pull out the whole harness to then find out that the wiring is under the seat.

Nope - I pulled out the driver seat, took the sill off, pulled up the carpet and there is 100% no relay, harness, or plug under that seat. That is when i checked the door tag and went "oh s^&$" :)
 
Can u tell me what colors the wires are at the relay on the shock towers.my pic shows a ac cutoff relay 11433

I'll look at them in the AM and let you know :nice:

nah, if he's running a 91 harness I am amazed he even got it to start at all.

90, if you cant find a harness send me a pm. I gotz one I was saving for a project.

I think i may be able to get one, im going to make a few calls tomorrow morning and i'll let you know. Thanks man! :nice:

My diagram shows 2 plugs underseat.fp relay and power lumbar .relay is green and it shows 2 wires grounded to floor

All i had under the seat was the plug for the power lumbar - there was also a ground bolted to the floor. I was the first one to take that seat out i can tell! :rlaugh: