accelerator to the floor cant go over 60 mph unless going downhill. no check engine light, have changed sparkplugs and coil plugs i can hear the motor rev up no smoke at all from tail pipe so far as i kno no blown piston rings. already checked fuel pressure regulator it is working. new hoses and new radiator as well as new alternator new serpentine belt. kickdown cable is set properly and accelerator cable is not stretched already ruled those out. i suspect speed sensor or a loose band in the transmission but haven't checked, beyond my expertise to do so. fuel pump and fuel filter are also working.
My car has 163000 miles.
My car has an automatic transmission.
It sounds like you may have a transmission issue. A worn clutch will feel like your wheels are spinning. The engine will rev up with no change in speed, when in gear. If acceleration is good through the first few gears but fails to accelerate in high gear, that is the band or clutch that has the issue. Unfortunately, you may have to find a used unit or rebuild the one you have.
If you'd like a second opinion on this, feel free to enlist a certified technician, such as one from YourMechanic, who can diagnose your loss of power firsthand. They'll be able to confirm my suspicion or suggest a fix from there. Best of luck.
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