car takes forever to get to 55 mph on flat ground loses up to 20 mph going up a hill if i floor it car makes high rev'ving sound but doesnt increase speed at all. changed sparkplugs and coil packs fuel filter and fuel pump all brand new. no check engine light no vacuum leaks either. transmission fluid looks the right color and doesnt smell burnt and just changed the oil, the new oil only has about 400 miles on it so far. catalytic converter is not clogged nor is any other part of the exhaust system that i know of. no smoke of any kind from exhaust pipe, piston rings and valves should be fine. besides a transmission problem what could cause this? two transmission shops say its not the transmission causing this.
My car has 163000 miles.
My car has an automatic transmission.
From what you've described, you could have clogged fuel injectors not giving enough fuel to the engine to produce power to go very fast. I suggest having the fuel injectors cleaned or replaced. The combustion chambers need to be cleaned in order to get carbon deposits off the valves.
If you need some help with this, consider YourMechanic, to get this fixed. A certified technician can help you diagnose your loss of power and help you replace your fuel injector if necessary. Good luck.
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