My car is 93z28 with 85k miles on it, I have this problem where my cranks for like 5-10 seconds before it starts, when the car is worm. The only way my car will fire up right away is when it sits for like 8 hours or longer or when I turn the car off and try to start it up to 15 min later the car will fire up right away. If the car sits like for 30 min after turning it off its going to crank forever to start up again (I tend to tap on the gas pedal to help the car start up faster but I don't think it does anything). I stored the car outside for like 5-6 months during winter and the car would fire up right away in spring.

I have tried to find out what the problem is myself for years but I end up with no answers. Here is everything I have tried.

I had shop do injector and fuel pump cleaning while back, because I store my car during winter and I thought the injectors were clogged. They hooked up this machine to the fuel system and ran some sort of cleaning solution thru the injectors and fuel pump for like 30 mins. That cost me like 350 dollars. Well after that the car ran awesome like never before, the car would fire up right away every time and I thought that the problem was fixed, but after few days I had fill up, so I do so and the same problem returned. I had the shop do the same cleaning another time after that like year later but this time it didn't do anything.

Then I heard that my injectors might be leaking causing the engine to flood and that would cause the hard starting. So I pulled fuel injector rail out and pressurized the system and looked for a leaking injector. There was few injectors were the fuel was collecting at the bottom but there was no injector leaking. The engine was cold when I tried this don't know if it would make any difference if the engine was worm.

I also had fuel pressure gauge hooked up the Schrader valve to see what the fuel pressure was like while the car was on and off. I noticed when the car is turned off that pressure would drop to zero from 40 psi in about 1-2 hours. I have tried starting the car with the fuel pressure gauge on after the car was sitting over night. The fuel pressure was at zero as soon the fuel pump would prime the system the fuel pressure would jump from zero to 40+ psi and the car would fire up right away.

I have talked to Brent Franker about this and he was not to sure what the problem is. He did say he read about this before and said that it could be ignition related not fuel related problem.

Any help on this problem would be greatly appreciated.
Thanks guys. Alex S

 

ttt

 

Ignition control module is my guess. I had one go out on me, and the car just died in the middle of the road. After it cooled off for a few hours, started right up. Once I changed it out, no more problems. If you do replace it, get a GM one, not one from Autozone.

 

Thanks, I will look into changing that. BTW how much does cost and how hard is to replace it.

 

not sure on price but it is easy to change. here it is http://shbox.com/1/coil_loc.jpg . thanks shoebox for all the trouble you go to, to post all those pics and write ups.

 

Well I have replaced the ignition control module with new one from GM dealership and that didn't do anything.

Anyone else know what it could be.