Camarokid95

I have a 95 Camaro z28 and when i start the car sometimes, when i turn the key to start it, the car will turn over but not fire up until i let off the key? Is this normal, sometimes it does it this way and other times it fires up without me letting off the key?

Injuneer

Try this.... before turning it to "start", turn the key back and forth a few times between "run" and "off". Then try to start it. If this improves the starting, it may be pointing to a problem with the fuel system losing pressure too fast, after the pump primes and shuts down. At that point you would check the fuel pressure to see what pressure it primes to when you turn the key to "run", and how fast the pressure drops off when the pump stops running.

Feenix

I had this problem awhile back and it ended up being the check valve in my fuel pump. It was sticking open and draining the fuel back into the tank rapidly so I didn't have much pressure during primes.

Camarokid95

Is the check valve part of the fuel pump?

Camarokid95

The car only has done it 2 times, both cold starts, as soon as i hit the key, the rpms go up but the car doesnt start until i start to let off the key, there is no delay in the starts, more than that split second or so, i've heard that if the check valve is bad the starts will be really delayed, i've run some seafoam through the car this summer to help clean the fuel system out, also i forgot to mention, around my hometown we mostly have 91 octane and a couple time lately i've added 93 octane (the only gas station in town that has it), to my 91 octane, would that have anything to do with the start? I wouldnt think so, because they would just mix, but it was a thought, any other time i start the car, as soon as i hit the key, it fires up, this car is not my dd and its gonna be sitting for winter real soon.

Feenix

Yeah it was in the fuel pump. And you're right about the long hard starts. When mine went out, my hard starts were terrible. As far as your issue, I am not sure honestly. My first thought would be ignition switch possibly, but i'd wait for someone who actually has a better idea.

Camarokid95

I'm not ruling out a fuel issue, my car has 103k on it and the pump hasnt been changed yet, ever since i got the car, i havent let the car go below the 3 quarter tank mark (actually about half a tank, the gauge just reads inaccurate), to try to make the pump live longer. When i went to start my car last night, my hand slipped off the ignition and the car acted like it was gonna start til it slipped off the first time (cold start) as soon as i hit the ignition the 2nd time it fired, but the security light was on for about another 3 seconds or so and then went out, the security light is not ever on that long, so idk why it was on a little longer that time.

Feenix

hmm wonder if the vats chip on the key is the culprit. Maybe do a lil research on it. Shoebox may chime in with some insight in time.

Injuneer

The SECURITY light would be on if its VATS.

Courtesy of Shoebox:

http://shbox.com/1/pass_key.html