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Should the A/C be turned off with the car?

  • Thread starter Thread starter sixstringthing
  • Start date Start date Jul 27, 2004
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sixstringthing

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Aug 11, 2003
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Jul 27, 2004
#1
  • Jul 27, 2004
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Someone told me a long time ago that it's good to set the A/C to the off position before turning off the car, otherwise you could eventually cause damage (to the a/c not the car) if you start it and it's on. True?
 

ToplessStang

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Mar 7, 2004
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Jul 27, 2004
#2
  • Jul 27, 2004
  • #2



The only thing you can do to help your a/c system is to run the blower motor for a few mins. in non-a/c mode before turning off the car in order to dry off the evap so that you don't get a nasty smell comming from the a/c after a few years. Even that is a pain in the A** and not really worth doing.
 
T

tarch

My 8V > 4V > 2V
Founding Member
Aug 20, 2002
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Jul 27, 2004
#3
  • Jul 27, 2004
  • #3
i do that too... everything is off, but the stereo before i park the car for the night
 

Cobra Jay

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Motor City
Jul 27, 2004
#4
  • Jul 27, 2004
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I try to make it a hibit of turning EVERYTHING OFF before I shut the car off.
 

merc123

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Jan 27, 2003
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North GA
Jul 27, 2004
#5
  • Jul 27, 2004
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I knew a guy in high school that left his a/c on and shut off his truck. His amp shorted out because of bad wiring and the truck kicked over and turned on the blower. It blew the fire into the cab of the truck and burned it down.
 
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vidmaster

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Jun 6, 2004
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Brick, NJ
Jul 27, 2004
#6
  • Jul 27, 2004
  • #6
if you crank the engine with the a/c on, it will eventually blow the compressor. thats why i always turn my key first without starting it. lets the fuel system pressurize and i also get to turn the a/c off if i left it on
 

twogts4us

15 Year Member
Apr 1, 2004
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Dunedin, FL
Jul 27, 2004
#7
  • Jul 27, 2004
  • #7
vidmaster said:
if you crank the engine with the a/c on, it will eventually blow the compressor. thats why i always turn my key first without starting it. lets the fuel system pressurize and i also get to turn the a/c off if i left it on
Click to expand...
Starting the car with the A/C on also puts extra strain on the starter motor. To me, it's just good habits to turn everything off before turning off the car - and starting the car with no accessories on.
 

wesl56

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Dec 26, 2003
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Tallahassee, FL
Jul 27, 2004
#8
  • Jul 27, 2004
  • #8
hmm, yeah i think this was discussed along time ago on here...

i usually turn mine off before parking for the night, but like if im just gettin out to run in a store or something, i usually forget and leave it on... but i dont know?


merc123 thats crazy! i had a truck burn down too, maybe that coulda happened to it too
 

Marks5.0!

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Jan 27, 2000
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San Antonio, TX
Jul 27, 2004
#9
  • Jul 27, 2004
  • #9
ive made it a habit to turn mine off when i get out of the car
 

Beau

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Jan 29, 2000
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Jul 28, 2004
#10
  • Jul 28, 2004
  • #10
i also turn off the A/C or even just the fan before turning off the engine.
 

SonicBlue2v03GT

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Mar 24, 2004
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You know its a Fact...San Diego is the greatest ci
Jul 28, 2004
#11
  • Jul 28, 2004
  • #11
Marks5.0! said:
ive made it a habit to turn mine off when i get out of the car
Click to expand...

Yeah, I have always done the same thing. Just habit. Not really worried about the stereo, no big amps or subs...
 

ChadS98GT

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Oct 22, 2001
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Jul 28, 2004
#12
  • Jul 28, 2004
  • #12
Yep I always turn my A/C off before I turn the car off.........as others have said...it's just a good idea....
 

Defleshed

Satanic Mechanic
Nov 30, 2003
10,569
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In Torment, In Hell
Jul 28, 2004
#13
  • Jul 28, 2004
  • #13
yep, i turn mine off too. Just because i like to hear my exhaust growl once before it's quite in the garage when I'm turning the car off and I have the car door open.
 

merc123

Active Member
Jan 27, 2003
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North GA
Jul 28, 2004
#14
  • Jul 28, 2004
  • #14
I rarely use my A/C

Problem solved.
 

propellerhead

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Apr 13, 2004
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"but what's with the but shots?"
Jul 28, 2004
#15
  • Jul 28, 2004
  • #15
The a/c doesn't run while you're starting the car.
 

Ryan02Stang

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Jun 17, 2003
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Arlington Heights, Illinois
Jul 28, 2004
#16
  • Jul 28, 2004
  • #16
Who uses A/C???
 

hognutz

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Nov 12, 2002
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Jul 28, 2004
#17
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there is no techincal merit behind this bs if you really think about it. when you turn the key to activate the starter power is cut for the ac/accessories so it does not have to compete for power. hence the clutch is not engaged. once you turn the key back from the start position then the power will make it to the clutch and the ac unit. then motor will then be running though.
 

hognutz

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Nov 12, 2002
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Jul 28, 2004
#18
  • Jul 28, 2004
  • #18
merc123 said:
I knew a guy in high school that left his a/c on and shut off his truck. His amp shorted out because of bad wiring and the truck kicked over and turned on the blower. It blew the fire into the cab of the truck and burned it down.
Click to expand...


I have a hard time following this story. I can't understand how the ac unit could have anything to do with starting a fire.
 

weldonGT

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Jul 15, 2004
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Jul 28, 2004
#19
  • Jul 28, 2004
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if you're not supposed to leave the a/c on when you turn off the car there are a bunch of luxury cars & etc that are in for a world of hurt (read, any car with auto climate control). The a/c in my wife's 04 Volvo never turns off due to the climate control, the fan just changes speed depending on temp.
 
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rjstaaf

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May 31, 2002
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Somewhere
Jul 28, 2004
#20
  • Jul 28, 2004
  • #20
hognutz said:
there is no techincal merit behind this bs if you really think about it. when you turn the key to activate the starter power is cut for the ac/accessories so it does not have to compete for power. hence the clutch is not engaged. once you turn the key back from the start position then the power will make it to the clutch and the ac unit. then motor will then be running though.
Click to expand...

This is exactly what I was thinking. The manual even states to leave the air set to A/C when you park so the car can breathe. When you shut the AC off you are cutting off all outside air to the interior and to the evaporator which will trap moisture and cause all sorts of little nasties to start growing in there.
 
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