Hi all,

I am hoping to get some suggestions as to what might have happened to my car this evening.

Car is as follows:

87 Iroc with 350 TPI

When leaving the local cruise night tonight the car started up fine and got as far as leaving the parking light. Without warning the car died and would not restart.

Everything was fine up to that point and it normally runs real good so it was a shock for this to happen.

Popped the hood and checked for loose connections, fluid levels, etc and no issues. One of the guys had an code scanner so we hooked it up and it flashed nothing but code 12 although it wouldn't start. The car cranks but never fires.

When turning the key and when doing the code reader I noticed the lack of hearing the fuel pump prime but it does not pull a code for it. We checked a buddies with similar car and could hear his pump prime with both the key turned to ON and also when initially pulling codes.

Obvious would be fuel pump or fuel pump related but based on no past sputtering or warning signs it is hard to believe the pump just up and gave out. Any suggestions on possible fuses, relays or other electrical issues related to the fuel pump that I should check first before the inevitable and dreaded fuel pump replacement.

Any suggestions would be greatly appreciated as the car now $120 later for a tow sits in my garage.

thanks
Scott

 

My buddys TA did the same thing we were out cruising and we pulled over to talk with some guys and he shut his car off and when we went to leave it wouldnt start. Would crank didnt hear fuel pump so we checked the line for pressure and it had pressure,so we gave up since it was like 1 in the morning and got it towed it turned out to be his spark controle module on the dist when it got hot then cold it died.
So u might want to check the fuel lines for pressure then check that little module thing.

 

If u have a good spark, the ign module is more than likely ok.

And u know the pickup coil is good too.(doesnt mean either or both didnt fail from getting hot and wokr when cold however)

Since your not eharing the fuel pump kick on whatsoever, I would check for spark real quick first.

Then jump the fuel pump relay and see what happens with a guage attached to the fuel rail and go from there,

later
Jeremy

 

I have an AFPR and it was showing pressure. It was erratic as it went as high as 55 psi when I was cranking it but it had pressure. Doing a search I heard that the fuel pump doesn't prime everytime if it has pressure.

I will check a few things today and keep you posted.

thanks

Scott

 

I relieved the pressure from the line and now my AFPR shows 0 pressure. Turned key to ignition on without starting it and listened. I can hear the relay click but still don't hear the pump prime. Turned the key and of course it didn't start. Still no pressure at the line.

What else can prevent the pump from priming without it actually being the pump that is dead. I have seen some debate on the oil pressure switch and sender units and my oil pressure gauge did act funny yesterday morning. I have checked the fuse on the front passenger fender and it is ok. I have checked all the wires leading from it visually and they are fine

My next step is to roll back the hatch carpet and check for current at the pump connections. If I have current then it would be pump. If not then the issue is before the pump. Is this the right way to go.

 

I'd ground your fuel pump relay at the A and G (I believe) at the ALDL and see if your relay kicks.

 

I didn't have much time to work on it today but I believe that I have ruled out it being a bad relay. I replaced the fuel pump relay at the end of last summer. I can hear it click when the pump should be doing it's prime stage. I also pulled the relay from the front by the battery which I have seen on this board is a suitable replacement and after swapping the two I can still here the click but no pump prime and no start.

Tomorrow night I will pull up the hatch carpet and see if there is power at the pump.

Any other suggestions??

 

Could possibly be bad oil pressure sending unit as well.

More likely just the pump, but just another thinig to check/keep in mind.

 

There are two oil pressure-related "sensors;" one is a sending unit for the gauge and the other is a switch that is wired inline with the fuel pump. Both are located at the rear of the engine, practically touching the firewall. The sending unit is the bell-shaped unit with one connector, while the switch is smaller and has two connectors. They should be connected together with a "tee."

The presence of oil pressure closes the circuit of the oil pressure switch, which in turn allows the fuel pump to turn on. I'd start by checking the operation of this switch while you crank the engine.

My fuel pump died last year without warning... one time it worked, the next time it didn't. The starter coincidentally went at the same time, leaving half of my car in the driveway and the other half on the street (at midnight, no less). That sure made for a long night .

 

Well I think I am getting closer and I might like the results better than a fuel pump. I tested the 3 wires at the pump to see if they were getting the 2 second prime pulse and got nothing. I tested the wire just in front of the fuse by the battery and got power, did same on the other side of the link right there and got power. I decided I should narrow out spark so I tested the wire off the coil and got no spark also tested #1 spark plug wire and no spark. I am now looking at a coil or the connectors to the coil.

I will test with a friend's coil tomorrow night and see if that cure's it.