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Air conditioner

Is there any ‘truth’ to the practice of making sure the A/C is in the off position before starting a vehicle? [reason suggested is that starting a vehicle with the A/C on puts an unnecessary/bad strain on the (cold) engine…]

Most modern cars have a disconnect for the A/C compressor until the engine runs. I used to always have the A/C off when starting the car in the past.

The “start” position of the ignition cylinder does not energize the relay for the AC compressor clutch in any modern car that I’m aware of. The AC is compressor is not engaged during starting.

I think Doc’s right, in the early days of AC this may not have been true, Heck, in my '61 Beetle the radio was even a seperate circuit and would remain on when you took the key out. It needed to be turned off seperately.

This is one of those things fathers teach us, because it mattered in “the old days.” Today it doesn’t matter at all if the AC is on or off. When you turn the key to the START position everything is disabled except the starter. Once the engine is running the extra load from the AC won’t hurt it.

Having said that, I always try to remember to turn everything off before I shut off the engine. Why? Because that’s the way my father taught me.

What type of effort would it take to put a end to these type of automotive myths? or do we want them to end and have nothing to write about?