I'm getting that notorious low idle engine shake problem now.

Sometimes the RPMS drop below 600 and the shaking starts.

Even if I turn the AC on, the RPMs stay at 600 or 700.

Any clues?

I don't want it to stall so I rev it when it does that.

 

Did you try bleeding the coolant? Most idle problems are the result of either a coolant or vacuum problem.

 

COOLANT???

that's a first.

 

My car tends to idle low, it doesn't shake really, but idles low, like under 500 at times. If I turn the AC on it goes to like 750. I can actually feel the the slightest vibration (unnoticeable 99% of the time) when the RPM's drop.