Car Vibrates @ certain speed/rpm
Hey Guys,
Hope someone can help me diagnose my problem...
Situation: Slight uphill, @ about 2.2k-2.5k revs....@ 80-85kmh
The car vibrates, when im accelerating...but when the vibrating starts.. i let go of the throttle and then the virbrating stops... and when i step on it again the vibrating starts again...this is only @ the speeds and rpms i mentioned above...
NB: Only happens in 4th gear.... say i manually shift to 3rd gear , and im still travelling at the same speed it no longer shakes..my mech friend says due to the lack of low end power?
Help guys? My car is auto btw..