Turning off AC before shutting off engine.

Is it just me being ocd and weird that I have to turn off my air conditioner before shutting my vehicle? Or, does it even matter?

 

I've shut mine off first for years and years.... back in the day it took some pressure off the compressor or something to that effect therefore making the ac system last longer....

 

"Back in the day" AC was a big deal and it required a significant of hp to operate. So, starting up the vehicle with the AC on would put stress on the starter battery etc. I think, and I could be wrong, the autos are engineered to take this all in to account now.

 

It has been my experience from multiple vehicles that if you don't run some outside air through the HVAC system before turning off the vehicle, that the next time you start up the vehicle, you will have the equivalent of baby barf odor emitting from your vents. Basically, moisture will condensate on the inside of your HVAC conduits if you don't vent, thereby allowing bacteria to multiply and prosper. This issue is especially bad when using max ac and recycling air instead of pulling air from outside the vehicle.

 

Does not matter. Do it or not.

 

Same here. I try to turn my A/C off about a min or so from the house, if I forget it smells like ass the next day for a couple min.

 

This! It may not happen right away but eventually it could happen and you will start getting a bad smell from your vents. I've seen numerous posts here and on other car forums with this problem occurring. Just get in the habit of turning off the A/C when you are a couple minutes away from your destination and let the fan blow to dry out any condensation in the system. It's easy to do and might save you a headache later on.

 

I leave it on running errands, shut it off about a mile before my destination if it will be sitting for an extended time.

 

I shut it off also. Including the ECT button lol

 

Doing this will prevent the dirty sock syndrome.

 

Then if you are running recirculation only for those few minutes, over time it's going to become an issue. It is very unfortunate, you'll end up breathing in mold spores...

Now, I'm not taking Toyota specifically, but that's an issue for most vehicles with Climate Control - whenever you turn it on it closes the flap and recilculates air.
Now days since this problem is more widespread, more shops are performing evap coil cleaning, when that stuff was happening to my wife's older Infiniti (nice few years ago) the stealership wanted to replace the coils $$$!

 

OCD OCD OCD.. I do the same as OP. Have no idea why. Sometimes I even turn off the radio but not always. Always turn off AC. Most times but not always I also turn off the lights. Sometimes but not always I leave windows open a crack. I always park between the lines or re-park. I sometimes but not always flex on Flex Friday.

 

Happened to mine. I though I had a leak from either the rear window or brake light like others. Pulled everything apart and was bone dry. I had remembered what a home A/C guy told me once about spraying Lysol to kill the mold in you system. So I tried that one night, and has been good since.

What is frustrating is the fact that the recirc mode comes on every time you start the truck. I have to turn it off manually every time, but I have not had the smell come back.

 

Yes, same here. When I think about it, I shut the AC off and leave the fan going a minute or two before turning the truck off. I remember my mom doing the same thing in her car when I was a kid. Yes, the reason is to minimize condensation remaining in the system. It probably isn't even helpful in the dry climate I live in because condensation rarely happens here. But OCD is a bitch and old habits are hard to break.

 

If you set the temp dial to just above the click before as cold as you can turn it, and turn off the ac and recirc before you turn off truck, the recirc wont come on when you start up the truck next time.

 

I do it but the only reason is so it doesn't start in the AM
when I leave.

 

I do it all the time.. I guess is my OCD as this action may not do anything good or bad to the AC or truck...

 

It IS important to turn off the fan so that it doesn't start on full blast the next time you start the truck and break that plastic fan attchment to the motor.

Plenty of reports about that. As a former airline pilot, I shut down everything before I turn off the truck. Just good housekeeping. Keeps thing from going "bang" on the next restart.

G.

 

I run windows down %90 of the time even down here in hot ass Tampa. When I do use the ac I switch between re-circulation and outside air.

 

Sometimes I briefly turn off my A/C when I enter a freeway onramp. I don't have to do this when I have ECT on. Damn 3.5..