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

  • Thread starter Thread starter 1990Coupe
  • Start date Start date Oct 18, 2008
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sscobra

20+ Year Stangneter
Oct 18, 2004
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Oct 20, 2008
#41
  • Oct 20, 2008
  • #41
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.
 

1990Coupe

Founding Member
Mar 11, 2002
1,462
132
114
Toms River NJ
Oct 20, 2008
#42
  • Oct 20, 2008
  • #42
sscobra said:
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.
Click to expand...

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?
 

1990Coupe

Founding Member
Mar 11, 2002
1,462
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114
Toms River NJ
Oct 20, 2008
#43
  • Oct 20, 2008
  • #43
sscobra said:
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.
Click to expand...

Yes im sure about this - the 02 harness plugged right into the 91 v8 harness
 

1990Coupe

Founding Member
Mar 11, 2002
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114
Toms River NJ
Oct 20, 2008
#44
  • Oct 20, 2008
  • #44
HISSIN50 said:
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.
Click to expand...

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.
 

sscobra

20+ Year Stangneter
Oct 18, 2004
28
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Oct 20, 2008
#45
  • Oct 20, 2008
  • #45
1990Coupe said:
Yes im sure about this - the 02 harness plugged right into the 91 v8 harness
Click to expand...


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.
 

hotcobra03

Active Member
Nov 29, 1999
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4
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poteet,tx
Oct 20, 2008
#46
  • Oct 20, 2008
  • #46
Can u tell me what colors the wires are at the relay on the shock towers
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
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gainesville
Oct 20, 2008
#47
  • Oct 20, 2008
  • #47
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.
 

1990Coupe

Founding Member
Mar 11, 2002
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Toms River NJ
Oct 20, 2008
#48
  • Oct 20, 2008
  • #48
I think i found the problem....

View attachment 296273

This would explain the horn going off, and no relay under the seat. My car was built February of 1992. This would mean it falls under the ladder part of 92, meaning the relays were relocated, meaning i need a harness for a 92-93 meaning i'm a fking RETARD





 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
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gainesville
Oct 20, 2008
#49
  • Oct 20, 2008
  • #49
sunnuva bitch


see if you can sell that harness for a 92-93 harness.
 

josh072692

New Member
Mar 24, 2008
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0
Greenville, SC
Oct 20, 2008
#50
  • Oct 20, 2008
  • #50
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.
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Oct 20, 2008
#51
  • Oct 20, 2008
  • #51
Can u tell me what colors the wires are at the relay on the shock towers.my pic shows a ac cutoff relay 11433
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Oct 20, 2008
#52
  • Oct 20, 2008
  • #52
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.
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Oct 20, 2008
#53
  • Oct 20, 2008
  • #53
My diagram shows 2 plugs underseat.fp relay and power lumbar .relay is green and it shows 2 wires grounded to floor
 

josh072692

New Member
Mar 24, 2008
16
0
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Greenville, SC
Oct 20, 2008
#54
  • Oct 20, 2008
  • #54
Cobra what year wiring diagram are you looking at?
 

1990Coupe

Founding Member
Mar 11, 2002
1,462
132
114
Toms River NJ
Oct 20, 2008
#55
  • Oct 20, 2008
  • #55
josh072692 said:
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.
Click to expand...

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^&$"
 

1990Coupe

Founding Member
Mar 11, 2002
1,462
132
114
Toms River NJ
Oct 20, 2008
#56
  • Oct 20, 2008
  • #56
hotcobra03 said:
Can u tell me what colors the wires are at the relay on the shock towers.my pic shows a ac cutoff relay 11433
Click to expand...

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

stykthyn said:
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.
Click to expand...

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!

hotcobra03 said:
My diagram shows 2 plugs underseat.fp relay and power lumbar .relay is green and it shows 2 wires grounded to floor
Click to expand...

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!
 

josh072692

New Member
Mar 24, 2008
16
0
0
Greenville, SC
Oct 20, 2008
#57
  • Oct 20, 2008
  • #57
Wow that sucks and you already updated your little profile thing at the bottom to say 92.
 

1990Coupe

Founding Member
Mar 11, 2002
1,462
132
114
Toms River NJ
Oct 20, 2008
#58
  • Oct 20, 2008
  • #58
josh072692 said:
Wow that sucks and you already updated your little profile thing at the bottom to say 92.
Click to expand...

Haha yea.. I was really bummed. (you can click the progress thread to see where i began)

I am so ready to start and drive the car, now i have to pull out all the wires and kinda start over there,

Thanks to EVERYONE for all your help!!
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Oct 20, 2008
#59
  • Oct 20, 2008
  • #59
My diagram shows 2 plugs underseat.fp relay and power lumbar .relay is green and it shows 2 wires grounded to floor
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Oct 20, 2008
#60
  • Oct 20, 2008
  • #60
Mine might be 2 early its .1988 ford shop manual,vol D powertrain group 24
 
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