Dear Car Talk:
Back when I was married, my ex-husband got upset when I turned on the car’s air conditioner while he was accelerating onto a freeway.
He said it was putting too much stress on the engine, and I should wait until he made it to “cruising” speed before turning the AC on.
I was wondering if he was correct about this. Anything you can advise is appreciated. Best regards — Carla
Still holding a grudge, eh?
Well, the bad news is he was getting upset at you all those years for no good reason, Carla.
The good news is he’s somebody else’s problem now, so who cares, right?
The air conditioner does use a good amount of power — and that power does come from the engine. But the engine manages demands for power quite well on its own.
So, when the throttle is wide open, or nearly wide open (when you’re accelerating hard), the engine automatically shuts off non-critical accessories like the air conditioner until you return to normal driving. Then, when there’s plenty of power to spare, it allows the air conditioner to come back on.
It happens in the background, so you probably never notice it. Obviously, your ex didn’t. But if you have the air conditioner on, and you suddenly floor the gas pedal to pass a Pete’s Pierogies delivery truck, your air conditioner’s compressor will actually drop out during that hard acceleration and then kick back in a moment later.
And it does so whether there’s an ex-husband in the driver’s seat getting upset or not. So, there’s no reason for you to ever think about this issue again as long as you live, Carla. Erase it from your mind. But if you do want to do a good deed, cut out this newspaper column and mail it anonymously to your ex’s next wife.
Got a question about cars? Write to Car Talk write to Ray in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email by visiting the Car Talk website at www.cartalk.com.
