I have a 99 Galant. Last night I got in the car and put it in reverse and the engine shook violently back and forth. It caused the entire car to "buck." The same happens to a lesser extent when the car is shifted into drive. There is a small increase in RPM when the car is shifted into gear (maybe a 150-200 RPM shift, I'm not sure if that is normal but its something I noticed). The car seems sluggish and it hesitates when accelerating from a complete stop.

This morning the check engine light came on. I had the sensors read and they came up with:

P0705-Transmission Range Sensor

P0715-Turbine Speed Sensor

P0720-Output Speed Sensor

The car is well maintained and I'm using the recommended transmission fuel type. Up until last night the car ran and idled beautifully and the transmission shifted with no noticeable problems.
Any ideas? Any help would be much appreciated.

 

Does anyone know what the problem is when this occurs? I am having the same problem.

 

Somewhat normal. Maybe an engine mount, but I doubt it.

You have those same check engine codes?

 

itdefineatly sounds like an engine mount. but that wouldnt explain the cel codes.unless its atransmission mount thats REALLY broken causing the trans to shift and throw these codes