Need help car starts but shuts off

MY 90 iroc will start up but then shuts off right away. if i give it gas it runs but the moment i get of the gas i shuts off. also 1 out of 10 times it might stay running but low idle. i changed the fuel filter in the rear thinking it was clogged but still no change. need help if anyone can.

Anytime you suspect fuel issue, use a fuel pressure gage. Some of the national brand autostores used to loan out a fuel pressure gage, if you don't have one. Also, check for any applicable trouble codes. Maybe you have an idle air problem, check the iac and tps, clean the throttle-body.

You posted about it not starting in another thread. Checks your VATS, specifically, the wire that runs to the ignition cylinder, make sure its not chaffed, or broken. Does the security light come on when it doesn't start?