Starter runs but L4 won't then first is look into oil fill hole and watch rockers move or not when someone turn the key.
No moving = cam gear is bad.
See my Cave,
Cam GearsMoves then follow normal steps...
Has Spark? Fuel flows at TBI? etc.
⚠️ Warning: Looking for spark the wrong way w/ DIS can hurt you and/or kill the "brick."
See my Cave,
DIS IgnitionHas spark but no fuel can be several things besides bad pump or wiring problems.
Because ECM can be "dead" but seems to work otherwise.
Factory Service Manuals are hard to read by most including most GM Dealer Service staff. AllDatadiy.com data is summery of that But near copy of GM FSM for given year and engine of whatever GM vehicle.
Haynes and Chilton books have big problems and missing data for 87 4 cyl like Haynes doesn't even mention DIS or 700 series TBI that your engine uses.
------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)The Ogre's Fiero Cave[This message has been edited by theogre (edited 11-13-2021).]