I have a 2001 Toyota Corolla 5 speed manual that is having a hard time picking up speed, but the engine will rev as high as your willing to push down the pedal. The engine runs well its just not affecting the speed of the car very quickly. We replaced the MAF sensor recently and it made little to no difference.
Your clutch is slipping and will not allow the engine power to get to the drive wheels. Do this test: Chock the rear wheels and put the handbrake on as hard as you can. Put the transmission in 5th gear. put in the clutch, start the engine, then slowly release the clutch. If the engine doesn’t stall, you need a new clutch.
thank you for the info! great help in figuring out whats going on.