So I have a manual 02 Chevy Cavalier with 147000 miles 2.2L. I have been noticing that when I fully step on the gas I get zero acceleration. It gets even worse when I'm in either 4th or 5th gear after 2500 RPM it will just start chugging along and I will even start to lose rpm and mph. I can't figure out what this could be. Thank you
There are Various Reasons as to why the car might not accelerate as expected , some of the most common faults for old vehicles are :
Faulty Timing Belt
This is one of the most common issues for old cars which causes improper or bad acceleration.Check if your timing belt is good.
Problem with O2 sensor
This sensor analyse the emissions which in turn affect the Air-Fuel mixture going into the engine, if this sensor goes bad then your ECU might think you are either running lean or rich and affect the acceleration.
Clogged up Air filter/Problem with Fuel filter.
If your car cant breath or consume fuel then it will not accelerate.Also as "rpmerf" says check if the exhaust for possible cats blocking the system.
If all the above work properly and car still does not accelerate properly then you need to check if your clutch is fine and its engaging properly and not slipping.
As a Side not check the Fuel pump for any possible issue , I had one such problem on an old ford not sure if its frequent.