Engine Performance problem
1993 Geo Storm 4 cyl Front Wheel Drive Automatic 147500 miles
----------------------------------------------------------------
when driving motor runs fine until have to throttle above 3500rpm motor then loses power til let up on throttle. have replaced plugs wires air and fuel filter also coil also have replaced entire exhaust header pipe back. also if u adjust distributor advance it gets a little better if u turn to retard timing it starts earlier.

Inspect and test the throttle position sensor/check for an excessive exhaust backpressure. also do a fuel pressure to rule out the fuel pump