Is the hot air tube even necessary?

Dear Car Talk

Dear Car Talk | Jan 01, 1992

Dear Tom and Ray:

I have a 1968 Mustang which I only use during the winter in southern Arizona. I took it to a local mechanic because I heard a rattle in the engine. His diagnosis was "hot air tube vibrating and making noise against air cleaner--remove to stop noise." He removed the part and discarded it without a replacement. He told me that the tube wasn't necessary. If not, why was it put there in the first place? And where can I get a new one?

RAY: The tube you're talking about runs from the exhaust manifold to the base of the air cleaner. And it's purpose is to bring warm air into the engine when the outside temperature is very low.

TOM: On very cold days, it helps make the car run better while it's warming up. And as we all know, Shirley, things shrink when they get cold. If you don't believe us, reach into your husbands swim trunks next time you two for a swim.

RAY: But since you only use this car in a warm climate, your mechanic is absolutely right in this case. You really don't need to replace it.

TOM: Of course, if you're looking for a hobby, you may want to spend the winter looking for one of these tubes. But if I were you, I'd just forget about it, and take up a more interesting hobby, like professional wrestling. Good luck, Shirley.

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