Idle Problem (loosing revs).

[Homebate]

Hey guys, I have a problem on my 2000 9-5, when i put the car in drive and lets say im at a stop light so my foot is on the break, the engine looses revs. (like its out to stall, I have an Automatic), the the revs. go back to normal, it does this about three of for times. Also I have noticed that the lights dim at the same time. If I put the car in Neutral it stops. This only happens when its in drive and im at a standstill. Has this ever happened to anyone else. Could you, pleas help?

[luv2drinkcoke]

Last time that happened to me, my car had gone into limp home mode. But you would have a cel if it was in limp home mode. I changed out my spark plugs and all was good.
When was the last time you cleaned your throttle body, changed the plugs, fuel filter, air filter and/or cleaned the maf and map sensors?

[Ivan]

If a vacuum hose slipped of to the brake booster, it will do that

[lesenyap]

mine does that a bit as well ,lights dim ,revs drop a bit ,but mine is a manual so not really noticable could be radiator fan kicking in ,or something else with a big power drain (air con)maybe.

[makingwaves]

I've been having this problem and most of the time when i turn off the ACC (or put it in neutral, but either way usually does the trick) it goes away... the ACC seems to be really putting alot of strain on the car actually.