hi

I dont know what is wrong with my car. Lately its been acting weird. my rpm go up and down sometime. for instance, my car is running fine but when i park at the signal, the rpm starts to go below 1000 rpm and my car shake really bad.
please give me some adv.
thanks

does it rev unusually high as well or does it just drop farther than normal at idle?

does it rev unusually high as well or does it just drop farther than normal at idle?


my standard rpm is around 1000..... it only drop below NORMAL( sometime lower than 500rpm). The rpm goes higher than normal only when i start the engine in the morning (it is normal for all cars i guess)

Only with the A/C on or not?

Only with the A/C on or not?


it goes up and down even when AC is off.