IN-95z28

I was driving my 95 z28 to work one day and the car started just fine... 5 minutes down the road the car just stopped running while i was driving. I cruised into a spot and proceeded to work by other means. I came back about 7 hours later and checked out a few things and then the car started finally and then died again 5 minutes later. SInce then the car will crank, but will not start whatsoever. I changed the fuel filter and checked the fluids and whatnot, but there is not much else i can do on my own without the right equipment. Also when the car died the engine coolant light came on and i checked it and filled it and is off now. It seems to me like their is no fuel getting to the engine or there is no spark? Any ideas or tips on how to check if these could be the problems? I really need this to get fixed asap :/
Thanks Guys!


I am not really good at car mechanics so I won't be able to try anything to out of the ordinary.

Injuneer

Scan it for codes.

IN-95z28

okay well i tried to go to a few shops and loan a scanner but no one had a scanner that would work with a 95... and the only one that did wouldnt loan them out... but i was looking today and thought about taking off the ignition control module and having that tested for free. this would help eliminate the ignition. I did manage to get the car started today, BUT it would only run for about 30 seconds then die... or if i hit the gas at all it would die. Any ideas? or should i just go buy a scanner still? thanks for the help guys

Injuneer

Check the fuel pressure.

IN-95z28

Do you have a link to a good list of instructions/tools needed to do this? I am beginner at this stuff. Sorry. Thanks for the help. And i am able to keep getting the car started if i turn the key "On" several times to keep priming the gas through.

IN-95z28

does anyone know where to find a OBD1 code scanner that would work with the 95 z28...? all the ones ive seen only work with a 95 Chevy Caprice and that is it... it says they wont work with any other 95 GM models... ive talked to 12 local auto stores and no one has one except for a ODB1 and OBD2 together for 301$... anyone got a link of a brand or something? or show me exactly what it should look like?

mpilarZ281992

Well, i dont know about 4th gens to much, but I just use a paper clip and connent to the A and B connectors located by my fuse box. I just read the codes by the number of flashes on my dash. But if you need to read your codes you could buy a OBD1 off of ebay or such.

Injuneer

93 was the last year LT1 you could flash the codes by shorting the ALDL pins. 94 and 95 require a real OBD-I scanner, or free scanning software. 94 uses the regular 12-pin OBD-I connector, but 95 has a 16-pin OBD-II connector, even though its an OBD-I PCM. You need an adapter plug for the scanner, or you need to use jumper wires as shown on Shoebox's page:

http://shbox.com/1/xraycable.jpg

AutoXray makes several OBD-I scanners, and you can often find them used for low $$$.

Software:

http://www.ttspowersystems.com/

http://www.andywhittaker.com/

Cable:

http://www.akmcables.com/

Silencer Rpms

hope you figure it out

Injuneer

Here's an Auto Xray for $70 on Amazon.

http://www.amazon.com/AutoXray-OBD-I.../dp/B000FNDNME

IN-95z28

okay well i had the fuel pump changed and the car runs now. Thanks for all the help guys. I have one more question though. To get the car to start i have to either prime the fuel pump several times or crank the engine for a long time while holding the gas down... could this just be not enough pressure at the beginning? Any ideas?

Injuneer

Check the fuel pressure. It sounds like the system is bleeding off the pressure too quickly after the pump primes. That could be caused by a bad check valve in the pump, a leak in the system (including the pump connection in the tank), faulty fuel pressure regulator, or leaking injectors.

Checking the fuel pressure requires only a "fuel pressure test gauge" available from any auto parts store. Its a pressure gauge with a hose attached to it, and the correct -4AN connector to attach to the Schrader valve on the fuel supply line.

http://shbox.com/1/fp_reg.jpg

Unscrew the black plastic cap, attach the test gauge connector.

Turn the key to "on" so the pump primes. It should go to over 40psi, and hold that pressure for a while after the pump stops. If the pressure drops immediately and significantly, you have one of the problems I listed. Since you had that problem before you changed the pump, and its still there, perhaps the pump wasn't the only problem. Checking the fuel pressure would have uncovered this problem.

After you start the engine, pull the vacuum line off the fuel pressure regulator (hold your finger over the end of the line to prevent a vacuum leak). While you have the vacuum line off, check for wet fuel - there shouldn't be any. Fuel pressure should be 43.5psi, with anything between 41-47psi meeting spec. Reattach the vacuum line and the fuel pressure will drop proportional to intake manifold vacuum. A 6 to 8psi drop below the "no vacuum" pressure is normal with a stock cam. Less drop with a more aggressive cam.

Tape the gauge to the outside of the windshield, take it out on the road, and check the pressure at WOT/max RPM. Should not drop below 40psi.

IN-95z28

Okay thanks for the help injuneer. I will test this tomorrow sometime and post the results. Thanks again, your explanation was very helpful!