Is it okay to let a car sit undriven for six months?

Dear Car Talk

Dear Car Talk | Mar 01, 1990

Dear Tom and Ray:

My son's 1979 Subaru station wagon will be parked at my house for six months while he is out of the country. What do I need to do to ensure it will run when he returns? How often should it be started? I don't want to drive it a lot, but will do what is necessary. It will be parked outside--not in the garage.

RAY: We don't blame you for not wanting to drive it, Judy. The good news is you don't have to. There's a common misconception that it's good to start a car and let it run for a few minutes every day. In fact, that's the worst thing you can do. Running the engine produces moisture, which condenses in the cold engine and cold exhaust system and produces rust. I haven't seen your son's car, but judging from other '79 Subarus, there probably isn't room for any more rust on it.

TOM: Here's what you should do. Before your son leaves, have him pour a can of gasoline stabilizer (like Sta-bil) into the tank. Then have him drive down to the post office and buy some air-mail envelopes. That ten minute drive will allow the stabilizer to work its way through the fuel system.

RAY: Then, while you're self-addressing the envelopes so he'll write to you while he's away, have him disconnect the battery and plug up both the tailpipe and the air intake. They can be covered with aluminum foil and secured with rubber bands. That will keep moisture (and small varmints) from getting into the engine. And that's it! Put the keys in his pocket and kiss him goodbye.

TOM: The only thing you should reconsider is whether you really want to park the car on the street rather than in the garage. Parking it in the garage won't help the car any, but keeping it hidden might protect the neighborhood property values over the next six months.

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