camarostripe96

ok my 96 trans am will not crank and i have a fuel pressure tester and i am fixing to test the fuel pressure!! what is the fuel pressure supposed to be on with the key just turned on and what is it supposed to be with the engine trying to start?

OBE1 95Z28

Primed with the engine off should be 41 - 46 psi.

camarostripe96

ok so do i hook up the guage or the guage and the hose thats on it, or what? also how do i tell if its a fuel regulator thats bad or whatever?

shoebox

How are you going to hook the gauge up without the hose? When regulators go bad, they usually leak fuel into the vacuum hose.

camarostripe96

ok well there is a hose which hooks to the shrader valve and it came with another hose but i figured it out its the bleed off hose ......but here is what happend , i hooked it up and turned on the key and it went all the way up to 43-44 psi and slowly backed off down to 35 of so......what is my problem?

Injuneer

If that was after the pump shut off, doesn't sound like you have a fuel problem..... 35psi is enough to start the engine.

camarostripe96

ok i got it started and now it is kind of a little rough idle. it threw a code P0100 says vaf a circuit malfunction, what is this? also my fuel pump after just turning the key on was running longer than normal w/ a loud whisling noise and did not stop till i turned the key off, what could that problem be?

Injuneer

P0100 = Mass Air Flow (MAF) insufficient signal activity

This code can set if the MAF sensor is faulty, or if the pink wire in the harness connector is not supplying +12V (when measured to the black/white wire in the connector). Could be as simple as a loose connector or a bent pin in the connector.

For codes, always check Shoebox's LT1 specific list:

http://shbox.com/1/Dtcs.htm

Z28LT1_Just_Nasty

Strange... I thought you had said that you had checked fuel pressure in your last thread and that you were not getting any pressure. Also thought you checked all your connectors.

Oh well, let us know what is is when you find out.

camarostripe96

no i never said i didnt have fuel pressure.....and i think it is cause my plugs are fouled out because of cracked wires i had that were broken..and i kept trying to start it and fouled the plugs out