What to do when car’s manual shift is acting up

DEAR CAR TALK: Today, as I released the clutch, I noticed that my car would start driving away like normal, even though my foot was never on the gas pedal. Instead of stalling out, as it normally would do if I didn’t give it gas, it just started moving, as if it had an automatic transmission. Any idea what’s going on? It’s a 2009 Subaru Outback. CAR TALK:

Actually, I’m not sure anything is wrong. If you’re good with a clutch, you can get most manual-transmission cars moving in gear without using the gas pedal. And most cars will go 10 mph or so without you stepping on the gas at all. But it sounds like you’re saying something has changed; I’m guessing it’s the idle speed. If you look at the tachometer, you may see the needle pointing to 1,300, 1,500 or 2,000 rpm instead of where it usually sits, probably a little below 1,000.

Why does that happen? It could be nothing more than the outside temperature. The computer will automatically raise the idle speed when you fifirst start the car in cold weather, to keep it from stalling. Under normal conditions, the idle speed will automatically drop back to normal once the car is warmed up — usually a few minutes, at most. But if it’s staying elevated, there could be a mechanical problem that’s caused your car to idle high. That’ll eventually make your Check Engine light come on — if it’s not already on by the time you read this.