I have a 94 Z28 with about 165,000 miles on it. About a month ago I took it out and when I bought it back I noticed coolant on the driveway. I pulled it the garage and took out the battery, hoses and radiator and intake tube w/ air cleaner. Didn't find any leaks so I put everything back together. Started car. let run for about 5 minutes. Stopped put more coolant in. Started car again which took a little longer to crank over but not bad. stopped to check coolant level. Couldn't get car to start at all. Couple days later started car. turned off. started again and drove it around. Wasn't too bad but it did sound like it missed or back fired a couple of times. Drove it around for about 15 minutes. Put it the garage and 2 hours later I went to take it out and couldn't get it to start. Three days later I got it to start after cranking for a while but it was running really rough and I had to keep giving it gas to keep it going. After that time I haven't been able to start it since. Cranks over so I think the battery and starter are fine (Both less then a year old). I also tried jumping it just to rule that out but that didn't work. I replaced the optispark around 100,000 miles and really don't want to do it again if I'm not positive thats it. Also tried starting it with the MAF sensor unplugged because someone on here said to try that. If anybody has any idea's I'd really appreciate it. I really don't feel like paying money to have it towed somewhere to pay more for someone else to fix it but I will if I have to. Thanks for reading and sorry for long post just trying to give as much info as possible. Also just trying to save my baby that I've had for 13 years but it may be time to set her free.

 

Does the engine crank, or is it hydro-locked? Pull your oil dipstick and see if the oil looks milky. If that's not it, then check to see if the water pump is leaking out of the weep hole. I hate to say it, but if the water pump is leaking, it's probably a bad opti.

 

The engine cranks over and over. Just don't hear it firing. No leak from the water pump. I did replace the water pump once before but that was probably 50,000 miles ago.

 

Well I would go through standard no-star diagnosis and go from there. Do you have fuel pressure? Do you have spark? Are the injectors pulsing?