While driving on the highway at 60 mph I went to pass a car and the rpm's went up but the car did not accelerate. It happened several more times. I got off the highway and took the streets the car accelerated to about 40 mph as long as I took it easy on the accelerator pedal. When I got over 40 it started bucking very badly. Made it home driving between 20-30 mph. Car has tranny fluid, the color is dark though, didn't smell burnt but I'm not a mechanic so who knows. Does this sound like I need a new tranny? Or something less?
My car has 178000 miles.
My car has an automatic transmission.
Hey there. This may be related to a fuel supply issue such as a dirty or failing mass air flow sensor. This is a unit in the intake system that reads the air flow into the engine as it is mixed with fuel before entering the motor. This info is relayed to the ECU which then makes a determination to increase or decrease the fuel supply. When this is not working properly, this may cause the car to react the way you have described due to the motor being over or under fueled. I would recommend having a professional from YourMechanic come to your location to diagnose the bucking problem so that this can be repaired correctly.
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