93 Mazda MX6 reving up and down when idling. . .

Question

Even if my car is warmed up every time I come to a stop my car starts to rev up and down usually between 2 and 4 on my RPM gauge but once I start driving again it stops. Does anyone know what the problem could be?

Answer 1

There can be several problems that can cause a hunting idle.  

A usual suspect would be a bad temperature sensor..  It may not let the ECU come out of high-idle properly.  Other sensors may contribute to this, too.

I'd get the system scanned at a dealership (assuming you don't have your own scanning device) to see if there are any sensor faults stored in the ECU.