I am picking up my new RX-8 in a few days and in advance I am reading the manual.

YA YA I know I am a GEEK... but thats okay because I love rotary's.

Back on topic...

Here is what the manual says on page 6-7 of the 2008 PDF for the RX-8.

"In the floor, defrost, floor/defrost positions, the air
conditioner is automatically turned on
(however, the indicator light does not
illuminate) and the position is
automatically selected to defrost the
windshield.

This item was also automatic on my Mazdaspeed Protege but someone figured out how to disable it.

See this link - How-To: Disabling Automatic A/C - Defrost modes

I know from personal experience that my gas mileage improved when I did this mod and I want to do the same thing with the RX-8... thinking that it will also improve gas mileage.

I am a big enough boy to know how to turn on my a/c when my windows fog, which usually only happens 2 or 3 days a year up here in Winnipeg.

So, the question...? does anyone know how to do this on an RX-8?

 

looks like I will have to change my sig... humm what to put

 

It should be the same. Once you get down there you can figure it out.

Anyhow, you aren't going to save any money.

People don't go driving around with there defrost on unlees your in snow country.

Besides it works better with it on.

 

that "feature" annoys me too... subscribed..

 

I don't recall, but someone might have already done this. In any case, I find it good enough to know that the face vent setting does not trigger the "like it or not" AC, so there is already a viable way to avoid.

 

There are a lot of us who live in snow country (like myself) and personally I prefer floor, or defrost/floor positions.. ( I hate air blowing on my face when I drive... dries out my contact covered eyes! )

About saving money, I think it will. It worked on my Protege and increased my gas mileage. I think if you can drive your vehicle and avoid the a/c from coming on, that in itself would give you better gas mileage. At least it does on every other car that I know of.

If we can figure this out and it works... WOW wouldn't it be great to get another mile or 2 per gallon...

 

^ exactly. esp in the winter after heating up the car by blasting the heat through the "face" vents i switch it to the window / defrost position..

 

As I understand it one of the reasons that cars engage the A/C pump while running the defroster is to give the A/C pump some activity (during winter for example when you wouldn't otherwise run A/C). Inactivity of that pump is bad for it, and if it is inactive for too long, it might no longer work.

It is possible that auto manufacturers have fixed this and it is no longer necessary to occasionally run A/C to extend its life, but I was told this a number of years ago. Something to think about/research.

 

I checked mine with a CANScan and found that the A/C cycles for a very short period, then has a long time between the next. Say 30 seconds between times when the A/C clutch is engaged and maybe engaged for 2-3 seconds max. Not a big deal.

 

It isn't only the warm air that clears the windows. Moisture in the air will cling to the cold windows. The AC removes moisture from the air.

 

So it's on about 10% of the time? Sounds like a big deal..

 

What about the floor/face combo position - is the Compressor on then?

 

Yeah,

I always put mine on "fresh air setting" and face

 

That's just what I remember, I don't have the exact numbers. Since you have a scanguage II why don't you see for yourself?

 

Running the a/c is highly recommended to ensure that the pump does not dry out.

Here is what the manual says... Page 6-1 from 2008 Manual

Run the air conditioner about 10 minutes
at least once a month to keep internal
parts lubricated.

10 minutes a month and I drive about 1200 minutes a month just for commuting to work.

That's .008% of the time I drive.

Way better then 10% while being operated automatically...

Please, someone, find out how we can disconnect the feature....

 

No,

Floor, defrost and floor/defrost settings only

 

In the Winnipeg winter, I would pull the a/c clutch fuse (10amp, near the front of the box) then the computer can do whatever it likes, the a/c won't kick in.


S

 

Interesting solution.... the only thing is, if you want a/c you have to stop, install the fuse... a bit of a pain if the car starts to frost on the inside and you want a quick 30 second a/c fix..

I will use your solution if there is now way to eliminate the auto function.

 

Just mount a switch somewhere that you can use to break (or not) the circuit that energizes the relay.

 

I might try this this weekend, got a 4 hour drive to DC so I can see any effect on mileage

 

If you disconnect it on the RX-8 the air from the climate control system will blow warm/hot ALL the time even with the fan **** turned to the zero position, including in the dead of summer

This is the only thing that bugged me when I had the AC deleted on my STU-class RX-8. If the AC isn't working you can't get cold outside air through the climate control system even if it's cold outside, this car actually uses the AC to cool outside air that must somehow get pre-heated by the engine is all I can figure

 

^ Hey, I have a working AC and half the time the cold air setting will roast me alive while the hot air setting won't heat worth a damn. Fun

 

Try a drive in one direction with a/c off (Fuse out)

The other direction with a/c fuse in.

I look forward to Mondays results

 

what brings you down to DC??

I work there and live and maryland

 

Yep, I intend to do this.. But I'm there for a week so results will take a while

I'm taking a training class in VA about 10 minutes outside of DC. You guys have any meets during the week?