Axeslinger0u812

1996 z28 was doing everything it could to start, but was immediately stalling after the initial fire. No excessive cranking, just crank, fire and stall. Fuel pressure checked out, it's getting spark, and all signs seemed to point to the opti. installed the new opti last week, and even with a weak battery, the car finally got started (it's been in the garage for three months). It idled fine while we were bleeding the air for the coolant, and everything seemed normal. I went to start it later that night, and the battery seemed really weak, and after idling for a couple minutes, it died. Figured the battery was at fault, because everything else seemed to check out. Just installed a new battery, and I'm right back at square one: crank, fire, stall. I don't know what else it could be. I absolutely love this car when it's running, but at this point, I'm making car payments for nothing, and I can't really afford that. Anyone have any ideas?

Guest47904

Is the security light on or blinking AFTER the pre start diagnostics?

You need a scanner to get codes.

Axeslinger0u812

Well, it randomly decided to start again, but I think the water pump also decided to go. Security light comes on and then goes off like normal, and I tried to get codes a couple months ago, prior to changing the opti, but the battery died at some point during that span, and seemed to clear any possible codes. It connected and scanned and I got no trouble codes. But now it's having issues staying at a regular temperature. I took it around the block, and the temp gauge was reading about 250. Shut it off, waited a few minutes and checked hoses, and they were cool. Bled the coolant screws again, and it seemed like the coolant started circulating, but it felt weak, and the hoses heated up. I'm thinking the no start might be a ground somewhere, if it's this intermittent. It's like I'm so close to getting it back, but it's not quite there.

kylew707

replace the coolant temp. sensor, the one that goes into the water pump. They are only about $20. That was the problem with mine. same symptoms as yours, plus it was running really rich and stumbling at stop signs etc. You can also try starting the car and unplug the sensor while its running if it stays running that long.

Axeslinger0u812

Ok, I'll give that a shot. Too much electrical components! Lol.

Another little bit of info I keep forgetting about because it's done it since I bought, but header gaskets are also leaking, and it's shooting sparks out occasionally. Any possibility that's affecting the compression enough for that sporadic starting behavior?

kylew707

I have never heard of that so i have no idea lol, when mine was doing this i had to hold the gas to the floor to get it to start. If i didnt it seemed like it had a weak battery like you are describing. Try holding the gas pedal to the floor and start it to see if that changes anything for ya

race u 2

How were u driving the car last time u had it out??? Pull dipstick check color of oil. I have came across similar issues helping a friend out and found a spun main. Pretty much car would start and die if it did start would run for a little bit and then die. Don't know if thats ur issue but it's a idea

Kevin Blown 95 TA

Header leaks that bad can let in oxygen and fool the O2 sensors and mess up your fueling - it might think it is running lean and add more fuel, so it is important to fix all of your exhaust leaks before the sensors and any other ones that are close behind them as well like collector leaks. You might pull some of the plugs on that side and see what they look like.

Axeslinger0u812

The oil is brand new. I smelled gas in the oil after all the attempts to start it prior to changing the opti. I also had to fix the main front seal because it was kicking oil all over the damn place. I noticed the seal in the opti had more or less disintegrated after I took it out, so I'm almost positive it was getting leaked into, but I haven't pulled it apart yet. Next week I should be changing the plugs and replacing the header gaskets, so hopefully that will help.

When I start the car and pull the thermostat sensor, what am I expecting to happen? Should it kick on the fans or start circulating coolant immediately? Ive only had two 3rd gen camaro's in high school and college, and this is the first time I've had an lt1 engine and also really done the work in the home garage. I had wanted to get more into the home repair side, but I guess I got a little more than I bargained for, lol, so bear with me.

GRIDERMAN87

you have to bleed the system through the bleed valves on your solid rad lines twist open while running the enigine and wait till it spits a steady stream. That is the proper way to blled out the system shoebox has step by step instructions on his site for all kinds of stuff.