AC compressor life

[3bears]

so first, I live where I hardly ever ever need ac. But I live where I need a defroster. When you use your defroster....it uses the ac compressor. (btw...I still have several feet of snow on the ground)
lately I have had a vibration at idle and figured it was the back road crappy gas stations I have to use. My idle would not hold constant, jumping between 700 and 1100 rpm. ( I cleaned the ICV and TB about 6 months ago) today I had to go to the flat lands about 2000k feet below where I live.
I turned the heater controls where there is no defrost icon.
Ide was perfect...about 6-700 rpm...no vibration
I'm at 175k on the 4runner

so what is the life expectancy of the ac compressor, and what is that gonna cost if that is the issue ?

 

[kolelt]

My 4Runner has over 200k and probably original AC compressor. With that said. It's normal for you engine to idle up and idle down when the AC is on. As for vibration. I don't know. Maybe you have a bad motor mount ? As AC kicks on. The engine revs up a little. As it turns off. The idle goes down. Every car basically does this.

 

[phattyduck]

How was it jumping between those two RPMs? A few seconds or longer at each?

The engine does idle-up when the AC compressor is on...

Maybe a problem with your AC controls if you have a limited?

-Charlie

 

[nobb]

When you use your defroster....it uses the ac compressor.

What do you mean by this? The HVAC systems on our 3rd gens are relatively "dumb" and I've never had the A/C turn on when the defroster does.

On my newer Hyundai, I have noticed that on a cold start on defrost mode, the A/C system will automatically kick in for the first few minutes then turn off itself. I've noticed this behavior on other new cars as well.

For A/C longevity on all my cars, I make sure to run the A/C for a minute every few weeks just to keep things lubricated. Rubber seals don't like sitting unused for long periods of time.

 

[tvpierce]

When the climate control system is on Defrost mode or Defrost/Floor mix mode the A/C is activated. The A/C button is irrelevant in either of these two modes. This is pretty much how all automotive climate control systems have operated in the last 20+ years.

There is a simple mod that can be done to manual (non-Limited) climate control systems that gives us control over whether A/C is activated in Defrost & Defrost/Mix mode. I've done it to my '02 Sport -- works well.

 

[19963.4lsr5]

Mr nobb The 97 Limited puppy hauler runs the AC in defrost mode.


Sent from my iPhone using Tapatalk

 

[kolelt]

Yes. AC does turn ON automatically when the defroster is on. Whether the AC button is pushed in or not.

 

[nissanh]

AC should come on with the defrost. It removes the condensation (humidity inside). My car has the factory AC compressor for its entire life. Still, works like new even after 25 years. The car has been on desert most of its life.

 

[3bears]

When the climate control system is on Defrost mode or Defrost/Floor mix mode the A/C is activated. The A/C button is irrelevant in either of these two modes. This is pretty much how all automotive climate control systems have operated in the last 20+ years.

There is a simple mod that can be done to manual (non-Limited) climate control systems that gives us control over whether A/C is activated in Defrost & Defrost/Mix mode. I've done it to my '02 Sport -- works well.

Ive got the manual heater controls.......
and the simple mod is....... ?

 

[tvpierce]

Ive got the manual heater controls.......
and the simple mod is....... ?

I can't take credit for coming up with this, but I've done it, and it works well.

https://www.tacomaworld.com/threads/defrost-without-a-c-mod.126495/

And before some blowhard chimes in to pontificate about the absolute necessity of AC for defrosting... understand that this is not permanently disabling AC during defrost mode. It is simply giving you the option of operating the defrost function with or without AC depending on conditions.

For instance in northern climates in the winter, the outside air is already nearly devoid of moisture, so no further drying of it is necessary -- all that's needed is outside air (already naturally dry) to be warmed and directed toward the windshield. This mod allows for this. But during the warmer seasons, you still have the option for the system to function with the AC activated if conditions warrant it.

 

[3bears]

I can't take credit for coming up with this, but I've done it, and it works well.

https://www.tacomaworld.com/threads/defrost-without-a-c-mod.126495/

And before some blowhard chimes in to pontificate about the absolute necessity of AC for defrosting... understand that this is not permanently disabling AC during defrost mode. It is simply giving you the option of operating the defrost function with or without AC depending on conditions.

For instance in northern climates in the winter, the outside air is already nearly devoid of moisture, so no further drying of it is necessary -- all that's needed is outside air (already naturally dry) to be warmed and directed toward the windshield. This mod allows for this. But during the warmer seasons, you still have the option for the system to function with the AC activated if conditions warrant it.

thanks, normally when people think of Oregon they think wet and wet air, but I live in the mountains where it snows a lot and it is often a "dry" snow

I see this mod in my future...(although my knob is a little different then the one in the write up).plus with the ac off even in defrost, it might help with mpg

 

[TheDurk]

I can't take credit for coming up with this, but I've done it, and it works well.

https://www.tacomaworld.com/threads/defrost-without-a-c-mod.126495/

And before some blowhard chimes in to pontificate about the absolute necessity of AC for defrosting... understand that this is not permanently disabling AC during defrost mode. It is simply giving you the option of operating the defrost function with or without AC depending on conditions.

For instance in northern climates in the winter, the outside air is already nearly devoid of moisture, so no further drying of it is necessary -- all that's needed is outside air (already naturally dry) to be warmed and directed toward the windshield. This mod allows for this. But during the warmer seasons, you still have the option for the system to function with the AC activated if conditions warrant it.

This. Cars had defrosters long before auto AC existed, and they worked just fine in the winter. Not so good in the summer. I'm old enough to remember cars with no AC, like my parents' '62 Olds station wagon and the '64 Corvair. Then my mom got the '66 Plymouth Belvedere (awful car, but with an AC that could freeze your lemons off.) The AC wasn't linked to the defrost for many years after that, I think the '85 BMW 7 Series is the first one I had that did that.

These factory Densos are very durable, and most of them will outlive the trucks they are in, especially if the systems are maintained leak-free and at proper charge and lubrication. A bad fill will kill one quickly.

 

[alumarine]

Is it possible to just splice a switch into the line that goes to the A/C clutch to achieve the same thing?

I'm thinking for me I could just deactivate the AC function for the entire winter.

 

[phattyduck]

Ive got the manual heater controls.......
and the simple mod is....... ?

Depends on the year. I believe with an 'early' SR5 you can also just unplug a single connector on the back (behind the blend knob). I'll be verifying this on mine in the near future (next time I'm in there to do the stereo).

-Charlie

 

[tvpierce]

thanks, normally when people think of Oregon they think wet and wet air, but I live in the mountains where it snows a lot and it is often a "dry" snow

I see this mod in my future...(although my knob is a little different then the one in the write up).plus with the ac off even in defrost, it might help with mpg

I haven't noticed an improvement in MPG, but I like not running something I don't need.

How is your knob different? I thought 2000-2002 were all the same.

 

[pluton]

This. Cars had defrosters long before auto AC existed, and they worked just fine in the winter. Not so good in the summer. I'm old enough to remember cars with no AC, like my parents' '62 Olds station wagon and the '64 Corvair. Then my mom got the '66 Plymouth Belvedere (awful car, but with an AC that could freeze your lemons off.) The AC wasn't linked to the defrost for many years after that, I think the '85 BMW 7 Series is the first one I had that did that.

These factory Densos are very durable, and most of them will outlive the trucks they are in, especially if the systems are maintained leak-free and at proper charge and lubrication. A bad fill will kill one quickly.

Good to hear about the Denso compressors upholding the company's reputation.
Out here in California, winter means rain and higher humidity inside the car. There were many occasions in the old non-A/C cars where you'd be trying to wipe the fog off of the inside of the windshield while driving in the rain. You couldn't run the heater/defrost at full heat because it'd get too hot in the car. So, whether or not A/C is useful in the winter depends on the local climate.

 

[tvpierce]

Good to hear about the Denso compressors upholding the company's reputation.
Out here in California, winter means rain and higher humidity inside the car. There were many occasions in the old non-A/C cars where you'd be trying to wipe the fog off of the inside of the windshield while driving in the rain. You couldn't run the heater/defrost at full heat because it'd get too hot in the car. So, whether or not A/C is useful in the winter depends on the local climate.

I'm of the opinion that adding choice and control to a system is generally a good thing. This mod doesn't eliminate anything, it simply gives the user an additional setting to chose which does not to activate AC while in defrost mode.
I fully appreciate the effectiveness of AC for defrosting -- it can be invaluable. For me personally (my use, in my climate), I only need it about 10% of the time. Yet I prefer to run the climate control in the defrost/floor mix mode because I don't want the air blowing directly on me. So again, for my usage, in my locale, this mod works very well. YMMV

 

[TheDurk]

Good to hear about the Denso compressors upholding the company's reputation.
Out here in California, winter means rain and higher humidity inside the car. There were many occasions in the old non-A/C cars where you'd be trying to wipe the fog off of the inside of the windshield while driving in the rain. You couldn't run the heater/defrost at full heat because it'd get too hot in the car. So, whether or not A/C is useful in the winter depends on the local climate.

I was talking about WINTER, not a California winter. Two different things.

 

[phattyduck]

I'm of the opinion that adding choice and control to a system is generally a good thing. This mod doesn't eliminate anything, it simply gives the user an additional setting to chose which does not to activate AC while in defrost mode.
I fully appreciate the effectiveness of AC for defrosting -- it can be invaluable. For me personally (my use, in my climate), I only need it about 10% of the time. Yet I prefer to run the climate control in the defrost/floor mix mode because I don't want the air blowing directly on me. So again, for my usage, in my locale, this mod works very well. YMMV

This is exactly my feeling. The defrost/floor mix is my favorite setting - fresh air, but not in my face.

I disabled the auto AC with defrost on my WRX, my old Camrys never had it and I will be disabling it on the 4Runner. I know when I need the AC to dry the air. Your average consumer doesn't, which is why it is always 'on' by default in new(er) cars.

-Charlie