I have a 2000 Chevy S10 with the zr2 package it has 127k miles and I've had it for about 6 months. I just use it for my lawn mowing business so I don't put many miles on it. every 3 weeks or so when I go to start it after finishing a lawn it sounds like it starts fine (fires over and then dies right away) so I turn the key and it goes up to 1000 rpms then dies within a half second. and I keep trying to start every 30 sec or so and it does the same thing for about 15 min then it will always just start normal. I have never had it not start agianI just have to keep try for awhile and it will finaly stay running. And when it happens sometimes it will happen 2 or 3 times in the same day and then I wont have any problem for the next 3 week. any ideas at all on what could cause this??? please help with any ideas or if you have had the same problem.
thanks

 

Sounds like a problem in the passlock system.
When it doesn't start, turn the key on, and watch the security light....does it flash? if so, leave the key on for an aditional 10 mins(or untill light stops flashing), turn key off, then start the vehicle.

 

sounds like it could be that. I think I do remember the security light flashing. what would cause this? or the problem in the passlock system? what does it mean when the security light flashes?

 

when the light flashes there is a problem in the system. Could be a wiring problem, module, but most likely the passlock sensor in the ign barrell

 

ok ill have to watch and see next time it happens. also yesterday when I was driving I notice that the security light was on while I was driving, it wasn't flashing just on. what does that mean?
thanks for your help!

 

So basically, is the light is flashing, it is in tamper mode and will not start. If it is on solid, there is a problem with the passlock system, a code has been set, and the system in in LEARN mode...trying to re-learn the resistances. But is there is a problem with the wiring or passlock sensor, is won't be able to re-learn it.