Javier97Z28

Update, fuel pump will be here today, install on Saturday.

Eliminated the relay (used the prime connector), fuel filter was fine...

shoebox

On the -96-97s the prime connector circuit also goes through the relay (not so on earlier years), so the relay could still be at fault. What you should be doing is confirming that voltage is being output from the relay to the pump during the times that you are not getting pressure (and when the relay should be energized). Since your problem is intermittent, you have to catch it when it is doing it to get a valid test. The problem could be your pump, but it would be a shame to go to all that trouble if it was not needed. Interesting...this is the first time I have seen this thread. I tried to reply earlier today, but there was something wrong with the board.

Javier97Z28

damn, and I wish I had seen this post earlier as well.

The car is now dead, it's no longer intermittent, I can reproduce the problem everytime.

Fuel pump (racetronix) is here and I ordered the upgraded harness which comes with a relay in the kit. I'm not sure if it's the same kind, but if it is I could do a quick switchout with them to see if that cures it.

Or, as you said, I could test the output from the relay.. where/which wire is the best to test that with? I'd like to avoid any cutting to get a voltmeter prong in there, so what would be a good place to try this. Can I stick the positive prong of the voltmeter in the fuel pump test port? If so, what kind of results should I get (voltage output and for how long)...

Lastly, will a dead relay "click" even if it's not working? I can hear my fuel pump relay "clicking" on when the ignition is turned on, and off after the two second prime period.

Hope you see this shoebox!

shoebox

I would put a meter on the power wire at the connector under the car that leads to the pump. Turn the key ON and see if you get power on the grey wire for 2 seconds.

Javier97Z28

I tried to use a voltmeter prong into the grey wire coming out of the relay but it's impossible to access from there. Tomorrow before I start the project I'll get under the car and try it that way.

I'm 99% sure it's not the relay though. I figure a relay is either on or off. Many times when I turn the key the pressure will only read 20psi... turn it off again, release, turn it back on, a little less than 20psi. Do it a couple more times and it's down to zero.

slopokrodrigez

The location Shoe is refering to is "under" the car at the connector located in front of the axle near the white plastic tank vent. The grey wire brings power up to the pump from there and is easy to get to. Shoe knows, check the supply voltage before you go tearing into anything. A lower voltage there under load(when the pump is running) however, could be bad wiring or a bad pump. One way to eliminate a wiring issue to the pump is to jump 12 volts directly to the grey wire.

Javier97Z28

Aight, about 50% done w/ this silly project.

Eliminated the power supply issue. Before we tore everything out I tested for 12V at the grey wire side of the terminal and received +12V for two seconds with the key turned on, power is getting to the pump. Tried it 4 or 5 times after making sure the car was not getting any fuel pressure consistently. So it's got to be the pump.

Got everything out, pretty easy really. Replaced the new pump into the bucket and let the glue dry overnight, which pushes my project to finish up next weekend (my buddies that are helping couldn't come back on Sunday).