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Whoop tube

The caller on today’s show mentioned his car bogging down sometimes and said the a mechanic once fixed this problem by replacing the “Whoop Tube”. I have hear the The vacuum hose from the intake manifold to the manifold absolute pressure (MAP) sensor refered to as the “whoop tube”. A hole or crack in this vacuum could result in the symptoms the caller described. The caller was wrong, of course, in describing the tube as being 2.5" in diameter.

Perhaps the “tube” that was cracked and allowing excess air to be drawn in was a tube from the air filter box to the intake manifold, beyond the mass airflow sensor. I’ve never heard the term “whoop tube”, but that’s the only tube I can think of that’s about 2.5" and in which a leak would allow excess air to be drawn in and the engine bog down.

My guess was the “Wide Open Throttle” or “kick down” rod was the issue. But Tom and Ray enjoy having fun and when the call is dripping with humor the technical details are overlooked.

I’ve never heard that term “whoop tube”. But I think @RodKnox may be on the money. On my 70’s Ford truck, there’s a sort of thick tube shaped thing-a-ma-jig that is operated by intake manifold vacuum I think. It’s purpose is to downshift the auto transmission when you step really hard on the gas. Like if you are going 40 mph in 3rd gear, and want to quickly accelerate to 70 mph to pass a car say, you step hard on the gas, and the transmission will downshift to 2nd to get you moving up to 70 faster. Prevents lugging. When I press hard on the gas like this, the engine revs and the transmission downshifts, and it makes sort of makes a “whoop” sound, so I could imagine that tube might be called a “whoop” tube by somebody. I don’t think that tube on my Ford truck contains anything though. Just an empty tube. It’s just a mechanical linkage from the carb/intake manifold area to the transmission. It was a fun call in any event.