Fuel pump not working
Race Director
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From: Whitefish Falls Ontario
St. Jude Donor '08-'09
If the fuel pump relay operates it will shut off the 12v on G to the fuel pump.. But if you had 12v from the fusible link to terminal E of the relay the pump would run when the relay operates..
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Race Director
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From: Database Error Indiana
The oil pressure switch is under the distributor to the driver side. After 5 or 10 seconds you should build enough oil pressure for the switch to power the fuel pump. Its easy to change. Also at the relay take a close look at the wire harness. On my 87 the wires got hot and shrunk back, a lot. 88s got better quality wire and I spliced in a newer terminal on mine.
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From: ft myers FL/Munising MI
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Drifting
Joined: Jun 2013
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From: ft myers FL/Munising MI
if your getting pressure by putting 12v at g and not when the key is on, i'd look to the relay or connections.....I think it's chart 7a in the fsm...I'd post it but not that computer friendly....you may have a loose connection in the tank...in my 85 those lines are just pushed into the pump and pulsator...a higher pressure pump could loosen them....did it to me...did a lot of head scratching until I found it....
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if your getting pressure by putting 12v at g and not when the key is on, i'd look to the relay or connections.....I think it's chart 7a in the fsm...I'd post it but not that computer friendly....you may have a loose connection in the tank...in my 85 those lines are just pushed into the pump and pulsator...a higher pressure pump could loosen them....did it to me...did a lot of head scratching until I found it....
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From: Whitefish Falls Ontario
St. Jude Donor '08-'09
First, does the relay operate when you turn the key on?? If yes then you need to check E of the fuel pump relay for 12v, if no 12v you need to check the fusible link that supplies power to it as I suggested in post #18..
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dosent operate with key on, never found the fusible link but i finally put in a toggle switch from one of the 12V wires under the dash and tapped into the fuel pump power wire coming into the fuse box
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From: Anaheim CA
The fusible link for the fuel pump also supplies power to the ECM. It is on a small wire that comes out of the positive battery terminal. It has a connector on it to reset the ECM. Here's what mine looks like:
In the diagram I posted above that connector is labelled "ECM POWER CONN. (NEAR BATTERY)".
You should be able to make the fuel pump run by shorting the contacts of the oil pressure switch. Unplug the connector (the one with the orange and red wires) and put a paper clip or wire into the connector contacts. The key does not have to be on to do this. If that doesn't work then you have a problem in the wiring or a connector somewhere.
In the diagram I posted above that connector is labelled "ECM POWER CONN. (NEAR BATTERY)".
You should be able to make the fuel pump run by shorting the contacts of the oil pressure switch. Unplug the connector (the one with the orange and red wires) and put a paper clip or wire into the connector contacts. The key does not have to be on to do this. If that doesn't work then you have a problem in the wiring or a connector somewhere.
Last edited by Cliff Harris; Nov 6, 2013 at 01:33 AM.
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The fusible link for the fuel pump also supplies power to the ECM. It is on a small wire that comes out of the positive battery terminal. It has a connector on it to reset the ECM. Here's what mine looks like:
In the diagram I posted above that connector is labelled "ECM POWER CONN. (NEAR BATTERY)".
You should be able to make the fuel pump run by shorting the contacts of the oil pressure switch. Unplug the connector (the one with the orange and red wires) and put a paper clip or wire into the connector contacts. The key does not have to be on to do this. If that doesn't work then you have a problem in the wiring or a connector somewhere.
In the diagram I posted above that connector is labelled "ECM POWER CONN. (NEAR BATTERY)".
You should be able to make the fuel pump run by shorting the contacts of the oil pressure switch. Unplug the connector (the one with the orange and red wires) and put a paper clip or wire into the connector contacts. The key does not have to be on to do this. If that doesn't work then you have a problem in the wiring or a connector somewhere.
Will try, currently running it with a toggle switch to the fuse panel
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From: Anaheim CA
The red wire in your picture is the one that goes to the connector I showed in post #34. It goes down to the splice where the orange wires come out.
I believe (not 100% certain) that the red "wire" is actually the fusible link. Maybe that's why it's bypassed.
I believe (not 100% certain) that the red "wire" is actually the fusible link. Maybe that's why it's bypassed.
