Recently this morning when I stop at the traffic light I noticed that my car started shaking and I look at the rpm and the needle been going up and down between 1000rpm and 1500rpm. Then later this afternoon I sat in my drive way I noticed rough idle again but this time the car was idling under 1000rpm. Maybe about 800-900rpm or so. It started sounding like it was gonna stall but it was fine when you rev it up. All rough idle happened when in neutral and in gear. I have clean the air filter and throttle body. I have reset the ecu but rough idle is still there. What might be the problem?

 

Dizzy is on good?

 

What?

 

dizzy = distributor i.e. cap/rotor/cabling and all that on tight.

 

Yeah its on there good.

 

Honestly, my car has always idled low like that, I used to ask her if it did it when she drove it and she said it always has. So I don't really even mess with it, I am sure i could have it idling higher, but the way I see it, the lower idle just saves a few cents on gas in the long run.

 

Well, with the needle bouncing up and down doesn't seem right.

 

how are your spark plugs? check engine light on? how long since you changed your O2 sensor? check for vacuum leaks.

 

Speak plug is good and there is no check engine light. Im not sure when was the the last time the 02 was changed. How do you check for vacuum leaks?

 

while the car is running, carefully try listening for any hissing sounds near intake gaskets/hoses, if you're lucky and there is a leak you can find it that way. if not you can spray carb cleaner over any intake gaskets/hoses and if the idle changes at all you've pinpointed the leak.