In D my car idles at 600 rpms, is that good or bad? If bad, what can i do to get it back up?

 

its fine, should be between 600-700 rpms
i think IACvalve screw adjustment can bring it up slightly if you want counter clockwise to increase idle, clockwise for decrease,

 

Cleaning your TB will raise the idle for a few days and then it should settle back to normal. I think 5-speeds should be around 600 and automatics should be around 700-750.

I have an auto and when I cleaned my TB, the idle was 900-1000 when the car was warmed up. After a few days, it went down to about 750.