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troubleshooting, EEC relay?

  • Thread starter Thread starter tannerc91gt
  • Start date Start date Jan 3, 2010

tannerc91gt

This last 25% is foreign territory at this point
Founding Member
Nov 29, 1999
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Indiana
Jan 3, 2010
#1
  • Jan 3, 2010
  • #1
long story...

just replaced my fuel pump with a 255 walbro unit last night. Also added a 6AL, coil and super conductors.

At first, fuel pump wouldnt prime at all. Dropped the tank (did it 6 times in the last 2 days) and made sure all connections were good on the pump itself.
Then i reviewed the "cranks but wont start" checklist, grabbed my multimeter and dug into EVERYTHING.

first off, no power to the connector at the fuel tank. So i checked the inertia switch and was only getting 2v with key on. Had a friend turn the key while i probed and ended up with more volts. So the inertia switch is also functional.

Moved up the relay.
Pink wire has 11.8, so it works. i removed the relay and jumped a few wires and was able to start the car, but obviously cant drive it that way.

replaced relay just to try it and it still didnt crank. A few random times the car started and just died after 15-30 seconds. Didnt sputter out, just instantly died.

Relay by MAF is functional and was clicking on and off when i was "jumping" the connector under the drivers seat.

does this sound like a bad EEC relay?


ive been working on this since 2pm yesterday.. starting to pull my hair out
 

apollo12

New Member
Dec 11, 2007
155
0
0
port st.lucie fla
Jan 4, 2010
#2
  • Jan 4, 2010
  • #2
Was the Mustang running before you put the fuel pump in? on the fuel pump relay you only need one wire to jump the switch. Sounds like a bad computer,do you have an extra computer to try?
 

tannerc91gt

This last 25% is foreign territory at this point
Founding Member
Nov 29, 1999
4,392
2,967
234
Indiana
Jan 4, 2010
#3
  • Jan 4, 2010
  • #3
I jumped it with 1 wire. Yes the car ran before. That's why i'm thinking it's the EEC relay
 

bgdowski

Member
Jan 11, 2007
62
0
6
Daytona Beach, FL
Jan 4, 2010
#4
  • Jan 4, 2010
  • #4
It seems like you may have it narrowed down to the EEC relay. Luckily, they are cheap, just throw one at it and see if thats it... It beats the hell out of continuing to troubleshoot.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jan 4, 2010
#5
  • Jan 4, 2010
  • #5
For people to help, we'd need to know what wires you jumped at a given relay.

If your injectors have 12V Key-on, the EEC relay is functional. That's not to say that a leg of the circuit isn't open.
 

tannerc91gt

This last 25% is foreign territory at this point
Founding Member
Nov 29, 1999
4,392
2,967
234
Indiana
Jan 4, 2010
#6
  • Jan 4, 2010
  • #6
Cant remember which wires I jumped(not helpful but it was 4am and Iwas very pissed)going to swap out EEC relays tommorow, altough I can't find a parts store that has one in the system, and if that doesn't work, I've got a friend with a A9L I can swap in
 
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