tech2

if the voltage to the pump is 12volts and the grd is good.....you need a fuel pump

dplantz

OK pulled the harness plug that goes up to the fuel pump in rear Grounded to frame and the purple wire ( assume that is the hot one) only registers 9v with ket on.... So may be a ground wire somewhere? Where is the ground located? Seems I also read somewhere there is a harness plug under the carpet. Keep advice coming!

dplantz

Ok so I found the wiring harness in the driver side kickpanel. All looks to be in good shape there, but had trouble getting any reading on my volt meter to either of the purple wires there, suppose not a good ground Also went up to Fuel relay fuse and it tested at 12v there Went back to back harness again and this time it tested 8v with key on....... So is it possible the pump can run but not at maximum strength due to only 9 volts getting to it, this the lower pressure readings?

tech2

unplug the connector at the fuel pump and check there. you may have to lower the fuel tank.

with key on you should have full battery voltage for 2seconds. Make sure your battery isn't getting low. If you do have a 3volt loss when testing with you voltmeter; as long as your sure your voltmeter grd is good, the problem is the power feed wire to the pump.

dplantz

Yes, that is where I was testing it. is it possible that by the time I turn on the key, get under the car and test that accounts for the 3 volt loss. I have tried to ensure I have a good ground....

tech2

you should only have voltage for the time the fuel pump is running; which should be for 2 seconds when the f/p relay energizes.

I'm looking at a 98model year schematic...the wire colour should be grey, 4 pin connector. the purple wire is for the fuel level sensor.

dplantz

Re the grey wire, the only wire that is "hot" in the 4 pin is the purple one Looks like the others are beiige ( or could be gray) Black and white one and then one black one

tech2

if you don't have power on the grey wire; that is your problem. check the fuse and relay. if you supply 12volts and grd to the fuel pump does it work?

dplantz

The fuel pump has worked all along and the car starts and runs most of the time. The problem is very intermittant. I still think the purple wire is the hot wire as this is a 96 so maybe they changed colors that year...? This morning I laid undeneath it while my wife cycled the key. One time I heard nothing, then the next time I can hear the pump running, but it is a very "faint" noise. I am used to my 98 Chevy truck, you can hear that thing fire up from the cab.....

dplantz

So I guess here is what I will try next cause I read it elsewhere.
Pull the fuel pump relay and clean the terminals and re-seat it
Check the voltage at the connecter in the trunk in the back ( the one that goes down to the pump) again
( I already checked the connecter in the drivers side kick panel, it looks all good)

As I said before though, folks keep telling me the grey wire is the hot one. I dont have a grey wire. I have a beige wire, a black and white wire, a black wire and a purple wire ( which is the only one I am getting a reading from of 9 volts. They must have changed the wire color from 96-97 to grey?