f1ctionZ28

I'm in need of help here guys. I've replace the relays, changed the fuel filter, measured the fuel pressure @40 psi with the ignition on, and 60 when the car is running. I'm running out of ideas. The car will crank and start the majority of the time and run flawlessly, however there are days in which she isn't having anyone's crap and just crank but no response. It's a 98 Z28. Any ideas before spending money on spark plugs and a new fuel pump?

dckmn52

before you go shotgunning parts at the car, check what is happening when its not starting.

is there spark, (crank sensor/cam sensor)
is there fuel pressure while its acting up.(pump)
is it getting air. (stuck TB, iac issue)

never know until you check everything over.