ive been having a problem since i bought the car. it would run sometimes and not others. I resoldered the main relay and tested it. I jumped pins 5+7 on the main relay harness and got a relay under the hood to jump but the fuel pump wouldnt start. with the main relay in place i turn the key to the second position and the check engine light comes on for 2 sec, then turns off, but i dont hear the pump prime. does this sound to you guys like ive definetly isolated the problem to the fuel pump?

 

another thing you can do to isolate the fuel pump is to unplug the fuel pump harness under the back seat, and check if you have voltage going to the pump according to the book. If you do, then it is most likely your pump, otherwise some wiring upstream is jacked up.

I suggested this just because replacing the fuel pump is a PITA at best, especially if it turns out to not be the problem..

 

the only harness under my back seat goes to the fuel sender i believe. my fuel pump is in my tank. can the wires be accessed from in the car for voltage? or do i have to drop the tank anyway just to get them?

 

The wires in the plug under the seat are for the pump. There are:

Yellow/white(fuel level)
Yellow/black (fuel pump signal)
And 1 or 2 black wires for ground depending on the year of the car. Probe the yel/black wire for voltage

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thevtecnician &raquo;</TD></TR><TR><TD CLASS="quote">The wires in the plug under the seat are for the pump. There are:

Yellow/white(fuel level)
Yellow/black (fuel pump signal)
And 1 or 2 black wires for ground depending on the year of the car. Probe the yel/black wire for voltage</TD></TR></TABLE>

That is correct..

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pimpwagon &raquo;</TD></TR><TR><TD CLASS="quote">the only harness under my back seat goes to the fuel sender i believe. my fuel pump is in my tank. can the wires be accessed from in the car for voltage? or do i have to drop the tank anyway just to get them?</TD></TR></TABLE>

you don't have to drop the tank to test the wiring for the fuel pump.. it is part of the wiring for the fuel sender harness. the black and yellow wire in that harness should be carrying voltage when the key is in the right position. definitely don't spend the time to drop the tank until you test that wiring.

 

this thing is killing me. im getting voltage. everytime i turn the key 2 clicks on i hear the pump prime. the car starts and stumbles but wont run more than 3 seconds. the fuel pump is running and then stops 2 or 3 seconds after the car completely dies. now it seems like the fuel pump might not be the problem. what else can i check for? is there a fitting i can put a fuel pressure gauge onto? i read something else about a possible distributor problem that could be the culprit. im getting desperate now. i bought this car because the a/c spits ice and its hotter than hell here, but i cant drive it. lol.

 

my next step would be to check the fuel pressure. you can do that through the service bolt on the fuel filter. you will need a fuel pressure guage, or you can buy a pressure test kit from sears or harbor freight. after that, you might check the fuel pressure regulator, depending on your findings.

If you are not getting a code, it is unlikely that your distributor is messed up, unless the rotor is loose..which you might check to rule it out.

Also, has the fuel filter been replaced recently?

 

i checked the rotor and its fine. the one thing that gets me is: if the car starts and im sitting in the driveway, it will run fine. i can start and shut down the motor as many times as i want. it only dies if i am stopping or turning. tomm i will check for fuel pressure at the output side of the fuel filter. i appreciate the help.

 

ok i finally said f--k it and dropped the tank. everything seems to be in order, except the sock on the bottom of the fuel pump is gone. the fuel pump had been changed and the mechanic tried to use the oem sock on a non oem pump. i replaced both and now it runs great.