Q: When in high RPMs engine drops in power and feels like it’s misfiring

asked by on March 31, 2018

I feel as though I am having a cam shaft sensor problem or the cam shaft synchronizer. When traveling at highway speeds the RPMS drop significantly and then will pick back up randomly. What do you think it could be?

My car has 139000 miles.
My car has an automatic transmission.

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A real time scanner is necessary to look at actual engine operating data and that will usually reveal enough clues to pinpoint the fault. Although the throttle control system is a common trouble area with reduced power or loss of power, there are quite a few other components and systems that could come into play and, of course, there is always the possibility of multiple, or "coincident", faults. Here are some of the possibilities that YourMechanic dispatched technicians would consider:


Defective throttle position (TP) sensor
Defective oxygen sensor
Defective accelerator pedal position (APP) sensor
Loose or damaged wiring
Defective throttle body
Defective powertrain control module (PCM) (not typical; ONLY if a long, long list of other possibilities is ruled out)
Any fault/error that will affect drivability function
Any fault/error that will affect vehicle performance
A fault/error in the emissions system
A fault/error in the throttle control system
A fault/error in the transmission control system


If you request an engine diagnostic, the mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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