Hey guys I've 1994 Camaro z28 that has me completely stumped the car will start fine but it will start to stumble and then recover but starts an idle at about 1500 rpms if I touch the gas at anytime of the drop in rpms It will die I've replaced o2 sensors throttle positioning sensor both coolant temp sensors idle air control valve fuel pump fuel filter plugs wires I've done a fuel pressure check and all checks out fine even during the rpm stumble I checked for vacuum leaks and found none and no check engine light during any of this if anyone has any advise it would be greatly appreciated thanks

 

I would try unplugging the mass air flow sensor and see if that stumble smooths out.

 

Did you replace the cap and rotor?

 

The cap and rotor have been replaced, but it was a couple years ago. Probably should replace it again. The car doesnt get driven like it should because of this problem. :/