1997 Chevy Cavalier Rough Idle and Lacks power

what were the sensors reading on the scan tool that you replaced

I can not recall the exact codes, the individual that read the codes indicated that it was the intake air sensor (this is the one that sits almost infront of the firewall) after replacing that one It then came back as being the throttle postion sensor. As previously stated, these have now been replaced. I also metered the plug wires and i am reading 8 - 10k of resistance. Replaced the plugs, also replaced the fuel filter, Removed the ignition modules and tested both came back good. replaced the fuel pressure regulator, Replaced the fuel Pump one month ago as the older one went bad, Opended the exhaust before the cataliytic converter and the same problem exists. I actually removed the intake manifold also, cleaned the ports and replaced the gaskets, visually checked the injectors and all looked fine, replaced the EGR valve. Checked for vacum leaks by spraying cab cleaner along the vacum lines no leaks present. Also I have checked the resistance of the injectors and eash measure about 12.2k of resistance the only other option I have is to take the injectors and have the thorugh cleaning done...Any other suggestions??

Ken

have you done a compression check. also with the scan tool find out what your fuel trim readings are.

Performed a compression test and all cylinders come in at around 121 very little variation from cylinder to cylinder. I would like to test the fuel pressure is there a method that I can use, that i dont have to cut the fuel line to insert my tool.

When the car start's it turns over immeditatly with no hesitation, So I am wondering if the fuel pump even though it is new is not delivering the correct pressure when the accelerator pedel is depressed, as the vehicle travels through its gears it slowly picks up more speed, though it does have a jumps as it goes from one gear to the other.

Thanks for your help.

Ken

you dont have to cut a line to check fuel pressure. they make adapters for this. did you check to see what your fuel trims are reading with a scan tool yet, it would also be nice to get any current codes that you may have

I will take the car this afternoon and see if the parts store is able to retrieve the trim code readings you are speaking of, the check engine light is not on at the moment on the vehicle, would there be codes on a different layer of the processor?

there should be codes in history