hi,
i have a 98 monte 3100 that is giving everyone a headache.

from beginning: died going down the road, no injector pulse. starts for less than one second and then dies. good spark, good fuel pressure, no codes. after much diagnostics and troubleshooting, reset computer out of desperation (disconnect battery overnight) it started right up next morning. ran great for 15-20 miles then shut off injectors again. replaced pcm and ran great immediately after for another day or so and same problem occured. switched back to original pcm, ran again. then same issue etc. no security light flashing, no codes, nothing. could this be security related?

 

Possibly. You check the fuel pump?

 

How's the alternator?

 

alternator and fuel pump check out. got a gm guy on it and we'll see what he comes up with.

 

Post what you find out. I'm interested in the outcome.