Hello all , I have a 1990 Chevrolet Camaro RS 305 V8. I had the motor rebuit about a year ago and have just recently got the whole car up and running. The car ran fine for the first few months of operation and then it started getting sluggish on me. It would be very slow to accelerate, and would sometimes stall out around turns. Return trips (when the motor was warmer) seemed to make this worse. I had the catalytic converter checked for blockage and everything was ok, but the mechanic there told me I needed a tune up. So I took the car in to replace the plugs, wires, distributor rotor, pcv valve, map sensor,coil, fuel and air filters. After the tune up the car ran beautiful, like it had the first few months after the motor was put back in. 2 Days later the car started acting up again. The same problems as before.I have a mild vibration or a shaking coming from the motor,and is very slow to accellerate. The stalling hasn't happened much since the car doesn't accelerate as fast now. Would anyone possibly be able to help me ?