Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
There is a good possibility that you have a fuel pump going out(low flow or pressure).You can check this by installing a fuel pressure gage at the filter connection & cycle the key a couple of times.Pressure should be around 12-15 psi & holding for at least 4 minutes.The flow can be checked by running an open fuel pressure line into a containers.It should pump a pint in less than 12 seconds.
Use a scan tool to inspect the ECM for failure codes & data.The throttle position sensor should be at .50 mv(at idle) & near 5.0 volts at wide open throttle.The manifold absolute pressure sensor should be 4.89 volts with key on/engine off-1.5 v to 2.2 at idle & voltage decreasing on acceleration.These 2 sensor are critical for an engine rpm response.
If this looks good pull a plug wire & install a spark tester in the plug wire(start the engine) end to make sure you are not losing spark.