Someone...please offer some advice:

91 Camaro RS with the 3.1 v6. I recently removed the throttle body and plenum to get better access to changing the coolant temp sensor and maybe check out the fuel injectors. The sensor was replaced...nothing was done to the injectors. The plenum and throttle body were reassembled with new gaskets.

OK...heres the problem. I now have no fuel pressure(can't hear the fuel pump whir for 2 seconds when cranking(cranks good). Before removing the plenum...the car would start up and run...everything was pretty good. I have checked and ruled out the fuel pump relay. The fuses on the fender and fuse block look good and have been swapped out. Could I have disconnected a ground or done something else when I had the plenum off? Is this a VATS related problem...despite the fact that it cranks. Thanks for any help.

 

I don't remember there being any grounds connected to the plenum fasteners. I can't honestly think of any connection between the plenum and the fuel pump circuit, aside from fuses. Of course look carefully for any pinched or disconnected wires. Did you plug everything back in? But I think I would have to go on from there to testing actual fuel pressure at the test port to verify no fuel pump operation. Then, go to testing the pump control circuit starting with power to the relay, then to the pump. Be sure to check for ground and power to the relay primary circuit. If you left a ground loose this test might reveal it. Unless the start enable relay has been bypassed, it's not likely a VATS issue.

 

Thanks for your prompt reply ASEdoc. There is no fuel(pressure) at the schrader valve at end of fuel rail. And again...I could hear the fuel pump if it was priming. Nothing. Right now I am trying to check power to the pump. I've jumped around the fuel pump relay and the switch on the oil pump relay(on the filter boss). Still nothing at the pump(no whir). Next I'll see what I've got at the 3 prong connector jump ahead of the fuel tank. Its hard to believe the the fuel pump would choose this time to go bad...as it was working fine before I dissassembled the plenum. No intermittant running or anything.

 

That would be a weird coincidence but certainly not the first I've seen.

 

Here is what I've done: Replaced the fuel pump relay...I have power to the fuel pump relay. Replaced the oil pump switch. Have jumped from the battery to the fuel pump bypass...no result. I don't have power at the 3 wire connection just ahead of the fuel tank. I have checked all the fuses in the fuse block...they are good. I was surprised to find a blown fuse on the inside fender...but replacing that didn't help. So...where to go? How many grounds could be involved? All the obvious ones either haven't been touched or look attached. Thanks again.

 

ASE DOC...in your previous post you stated: Be sure to check for ground and power to the relay primary circuit. Please explain exactly how this is done. Components involved, how to test for a ground? Thanks.