2000 Ford Taurus Car Revs up while on the brake

AC compressoris used with the defroster. Because the compressor adds an extra load to the engine, some cars compensate by raising the RPM so the engine doesn't die. Now this should be minimal and not cause you to slam the brake through the floor to hold still.

Let me know if this helps or if you have other questions.

Joe

It has changed to a higher rpm (about 1400 rpm) for about 5 seconds and the car will physically move.

Yesterday, I sat on my driveway on "drive" without my foot on the brake or gas. When I put the defrost on, after a few seconds, the car "revs" up and physically moves itself.

Is it just an adjustment I need or a part? How much would this cost?

Thank you for your help.
Susanna

when you say it moves, is it just slightly, or does it take off like you hit the gas? If just slightly, chances are it is normal.

It is not slight but not dramatic as if I slammed the gas.

I was at a stop sign and had to make a left during heavy traffic so I have to be quick. I had my foot lightly on the brake and if I didn't slam the brake all the way down, it would have taken me 2 feet into traffic.

It moves about a foot or two during this "reving up-which only last a few seconds" It happens in intervals of every minute or two.

Has the check engine light ever come on? It sounds like a throttle position sensor (TPS) or idle air control valve (IAC). I can't be sure without a check engine light.

The check engine light has never come on.

You may want to have the computer scanned regardless of the light. Most nationally recognized parts stores will do it for free, so there is no money out of pocket. It sounds like one of the items I described, but I can only guess without having the computer scanned.

Thank you so much for all your advice - you have been very helpful and prompt in responding to my questions!

Suzi