This is topic fuel pump wont prime in forum Tech Talk at Northern California Ford Owners .
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Posted by triple b (Member # 8763) on
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I think fuel pump or my ECU quit. 1988 5.0 turns over no fuel pump prime no fuel pressure. Checked the fuseable like at the ingition cylinoid-12volts, checked the relay under seat org/grn wire 12volts, checked the interia switch 5volts in/out, checked the fuel pump yellow wire 5 bolts, pink/black wire 0 volts..... tried to jump power from yellow wire to pink/blk wire nothing happened. I also ran a jumper on the test port to run the pump ....nothing happened and 0 volts on pink/blk wire .... what u guy think, I also recently smell/saw smoke cant tell if it was from driver/passenger side...
Posted by *Als50* (Member # 6003) on
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Change-out the relay under the seat 1st.
Posted by rollininmy50 (Member # 9067) on
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How's the ignition solenoid? Is it loose, coming apart? Or keep,checking for a short
Posted by triple b (Member # 8763) on
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ignition was loose 2 yrs ago I zip-tied it to the column and it holding....I took off the driver seat and jumped a wire across the pink/black from the orange/blue and got the pump to prime and had 40psi on my gauge...so then I tried to start it jumped over but no luck..it usually starts every time. so then I checked my injector harness it has 5 volts major loss should be 12 volts right whats next to do? Can my computer be the whole problem or is there a gremlin in the wiring ignition
[ 2014-03-07, 11:17 AM: Message edited by: triple b ]
Posted by triple b (Member # 8763) on
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quote:
Originally posted by *Als50*:
Change-out the relay under the seat 1st.
did that too easy but it not that... I should add I did the 4cyl swap on this my self...and have switched everything correct, sensors, vacume lines, even the 02 wire harness for the correct computer it smogs x4 since the swap at any station and it has major bolt-on upgrades
[ 2014-03-07, 11:16 AM: Message edited by: triple b ]
Posted by triple b (Member # 8763) on
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FML after searching and searching I found another relay...it is the ECM relay that apparently powers the fuel pump relay and injector harness so i pull it above the ECM and it was green and corroded so off to autozone I go..
Posted by triple b (Member # 8763) on
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Runssss! F$&King relay on top of relay in this dam car! Who knew that the foxbody fuel pump relay under the seat is also powered by another circuit that is interrupted by the ECC relay, ECU relay, ECM relay, whatever u f'ning call it relay next to the ECM! The low voltage at my inertia switch and and fuel injectors gave it away but changing out the fuel pump relay did nothing...it was the ECM relay the whole time. Just think I was looking to replace my walbro pump and A9L ECM to try to fix a $20 dollar relay.
Posted by LXjames (Member # 10791) on
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Some good ass info right there
Posted by Tom Renzo (Member # 13165) on
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YEP the EEC relay controls the whole thing. Easiest way to tell if the EEC relay is shot is a 2 second test!!! Key the car on and see if the CEL light comes on. if not chances are the EEC relay went south. A 2 second test and you are dun!! No EEC relay NO ses light on the dash no pump and no injector pulses. Easiest thing in the world to test!!
[ 2014-03-08, 05:39 AM: Message edited by: Tom Renzo ]
Posted by triple b (Member # 8763) on
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^ no check engine light would come on usually goes off after the car starts...but my car would not start. my car would turn over as many times as i wanted just no power to fuel pump and low voltage to the inertia switch and injectors it never threw a code also the test port was jumped and i had no power also [EMAIL]
[ 2014-03-08, 12:26 PM: Message edited by: triple b ]
Posted by Tom Renzo (Member # 13165) on
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NOPE!!!! You can not have a check engine light with a defective EEC relay. The EEC relay powers up the ECM. No power to the ECM NO CEL LAMP. Simple troubleshooting.keying the car and the engine not running or will not start will still illuminate the CEL light. If not the ECM is not powering up and most likely the EEC RELAY. If you doubt this remove the EEC relay and try it!!!!
[ 2014-03-08, 02:15 PM: Message edited by: Tom Renzo ]
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