I'm asking because my car has been idling low when I let off the clutch. For example, I'll be driving down the road with no problems, but as I brake and depress the clutch while approaching a stop sign, the idle will dive down real low. It is low enough to make the engine run rough, and though it has not stalled yet, I wouldnt be suprised. I recently did a tune up on the car, maybe 3 weeks ago. I do not suspect anything there because the car ran flawlessly up until yesterday. I installed a new cap, rotor, plugs, wires, air filter and PVC valve. I have the fuel filter, but its too cold to lay down in the driveway and do that just yet lol. I do not suspect the fuel filter, because I believe that gives problems under heavy acceleration when it is clogged. Also, this only happens when the engine is fully warmed, not when cold. This leaves me to rule out a bad EGR valve or solenoid (if these cars have an EGR solenoid...). I'm sure there is some sort of idle air control valve, but what else is involved in maintaining of idle speed? I have not yet checked for vacuum leaks, but I suppose I should do that as well. What role would the O2 sensor play in this? I'm sure it could use a changing also. Thanks in advance!!