What do you guys think of the RX-8 A/C unit on the hotest days?
Mazda Only. 10+yrs
Joined: Nov 2006
Posts: 189
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From: Reading PA
One of the first things i ripped off my '85 rx7 was the AC compressor and the parts associated w/ it .... I wont use the AC on my '8 until needed.
But:::: Funny you should mention how it cycles funny .... we have a '05 Ford van at work and the AC acts exactly as you describe in that POS. ... I wonder if the "crappy" AC is due to Fords influence!
But:::: Funny you should mention how it cycles funny .... we have a '05 Ford van at work and the AC acts exactly as you describe in that POS. ... I wonder if the "crappy" AC is due to Fords influence!
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Joined: May 2007
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From: Florida
Thread Starter
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One of the first things i ripped off my '85 rx7 was the AC compressor and the parts associated w/ it .... I wont use the AC on my '8 until needed.
But:::: Funny you should mention how it cycles funny .... we have a '05 Ford van at work and the AC acts exactly as you describe in that POS. ... I wonder if the "crappy" AC is due to Fords influence!
But:::: Funny you should mention how it cycles funny .... we have a '05 Ford van at work and the AC acts exactly as you describe in that POS. ... I wonder if the "crappy" AC is due to Fords influence!
Ford makes a great A/C system it'll freeze your bons off in their LTDs, Focus, P/Us, SUVs/Mazda's Explorer and Mustangs so maybe its a 3rd party suppling the A/C units for the RX-8. Now the chrome plastic seems to come off and break but generally their A/C units are fine. How many auto Companies does Ford have interest in now Jaguar, Mazda, Rolls Royce and ...
Last edited by donack456; May 30, 2007 at 08:35 AM.
the enemy in the mirror
Joined: Oct 2006
Posts: 440
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From: billerica, ma
rev up the engine a little extra to make the most of the compressor's three seconds on, three seconds off. :-P
my 04 works ok.
on humid days i've seen clouds come out! (but i should keep my eyes on the road)
it does do the cycle.
my [limited] understanding was that since it is belt driven, and the rpm's go way up on the '8 the a/c clutch on/off cycle was to protect the mechanism (bearing or whatever) from wear - not to prevent the core from freezing. they don't want the a/c systems dying for people that drive around at the redline all day...
i suppose mazda could've installed a mini gear system and sized the a/c to run in a smaller rpm range.
--
any thoughts?
my 04 works ok.
on humid days i've seen clouds come out! (but i should keep my eyes on the road)
it does do the cycle.
my [limited] understanding was that since it is belt driven, and the rpm's go way up on the '8 the a/c clutch on/off cycle was to protect the mechanism (bearing or whatever) from wear - not to prevent the core from freezing. they don't want the a/c systems dying for people that drive around at the redline all day...
i suppose mazda could've installed a mini gear system and sized the a/c to run in a smaller rpm range.
--
any thoughts?
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Joined: May 2007
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Other than the fact it goes from cool.....to cold and back it seems ok. I have always just rolled down the windows in all of my cars so I will probably never really know how good it is unless the wife is with me
Banned
Joined: Jan 2007
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I never use it. In fact, I HATE the feel of a car with the AC turned on, in anything less than an SUV or a E or S class, every car feels lethargic to me. But when I do use it, it seems perfectly fine. Mind you its only a few months old, so it should be at its best right now.
Anything is better than my old 240sx. Used to spike the temp gauge all the way to pegged-red when I switched it on; either under load or sitting still. Took me at least six months to figure out it was just bad wiring, and that my water temps weren't sky rocketing. :foreheadslap:
Anything is better than my old 240sx. Used to spike the temp gauge all the way to pegged-red when I switched it on; either under load or sitting still. Took me at least six months to figure out it was just bad wiring, and that my water temps weren't sky rocketing. :foreheadslap:
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Joined: May 2007
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From: Long Point, Ontario, Canada
Well I finally drove my 8 today in hot weather 30c (86F). I was with my mother, sister and her month old baby. Got in to the car extremely hot, been sitting out in the sun most the day. Opened the windows turned the ac on full on just the dash vents, and then closed the windows once we were moving. 3min down the road my sister was complaining it was to hot for her new child. I was concerned, thinking damn this isn’t going to be good “after hearing all the rumors the ac is horrible in the 8” but another 7 min she was complaining it was now too cold. I spent about 3 hours driving various places to day and it was more than adequate and I do not have the ac booster.
Surf Hard, Drive Hard
Joined: Feb 2007
Posts: 7,840
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From: Indialantic, Florida
Sorry, been out of town last day or two. I don't know....I'll try it that max thing and let you know what happens. My car sits in the hot Florida sun all day long at work. I get in and it's cool before I have driven two minutes. I am on re-circulate but I hardly ever have to turn the fan past the very first(low setting) setting. My compressor doesn't cycle on and off quickly either......as some have pointed out. I do someone where I work that has an 06 Mazda 6 and his air sucks! Will blow cold one minute and then hot the next.
Last edited by Mazurfer; May 30, 2007 at 07:01 PM.
The a/c in my 04 sucks. Whether at idle or on the highway, it gets cold, then warm...then cold, then warm, in 5 second intervals. For the short time that it is cold, it is very nice.
The issue here is that the a/c compressor (and cooling fan) is kicking off and on, off and on. After doing a little investigation in the FSM there is apparently a computer for the system called the a/c amplifier that looks at several sensor inputs and determines what to do with the a/c. For whatever reason, this system is choosing to have the compressor behave this way. The FSM states that this is "normal operation" but I think it is forking retarded. There is no reason to have the a/c compressor turn off when the controls are set at max, unless the inside core is freezing...and I can tell you there's no way that is the case because the inside of the car is not that cool.
I have went so far as to jumper a test wire from the compressor to battery power while the engine is running and performance is MUCH improved. However I have not had the ***** to leave it that way at this time until I can do more investigation on what other issues may arise. Part of the problem is that the control switch from the dash seems to operate on 3vdc instead of 12vdc, so using this switch to control a power supply or relay to the compressor will be difficult, and I dont want to ghetto rig any extra switches in the car.
The issue here is that the a/c compressor (and cooling fan) is kicking off and on, off and on. After doing a little investigation in the FSM there is apparently a computer for the system called the a/c amplifier that looks at several sensor inputs and determines what to do with the a/c. For whatever reason, this system is choosing to have the compressor behave this way. The FSM states that this is "normal operation" but I think it is forking retarded. There is no reason to have the a/c compressor turn off when the controls are set at max, unless the inside core is freezing...and I can tell you there's no way that is the case because the inside of the car is not that cool.
I have went so far as to jumper a test wire from the compressor to battery power while the engine is running and performance is MUCH improved. However I have not had the ***** to leave it that way at this time until I can do more investigation on what other issues may arise. Part of the problem is that the control switch from the dash seems to operate on 3vdc instead of 12vdc, so using this switch to control a power supply or relay to the compressor will be difficult, and I dont want to ghetto rig any extra switches in the car.
beers
Thanks for the link and suggestion. But...I am a mechanic and engine builder...I am not stupid. I know how to set a/c controls to max. Even when this is done, the air gets cool then warm, cool then warm, as the compressor cycles on and off at perfect ~5 second intervals. This happens at idle or driving 55mph down the road.
That MAY be normal operation for rx-8 cars, but it is NOT normal operation for car a/c systems in general. Ive owned and worked on hundreds of FC and FD rx-7s, a millenia, s-10, older Denali, current Denali, silverado, grand am, escort, the list goes on.
Every properly working (and cold) a/c system runs for 2-5 minutes and cuts off for 15-60 seconds then starts again. They only cut off because the core is getting too cold and there's no need to cool it further. They do not cycle RAPIDLY off and on without ever letting the core get cold, which is exactly what the rx-8 is doing.
If I can only figure out a way to keep the compressor running longer on the rx-8 without harming anything else, the a/c will be MUCH improved.
That MAY be normal operation for rx-8 cars, but it is NOT normal operation for car a/c systems in general. Ive owned and worked on hundreds of FC and FD rx-7s, a millenia, s-10, older Denali, current Denali, silverado, grand am, escort, the list goes on.
Every properly working (and cold) a/c system runs for 2-5 minutes and cuts off for 15-60 seconds then starts again. They only cut off because the core is getting too cold and there's no need to cool it further. They do not cycle RAPIDLY off and on without ever letting the core get cold, which is exactly what the rx-8 is doing.
If I can only figure out a way to keep the compressor running longer on the rx-8 without harming anything else, the a/c will be MUCH improved.
beers
Rotary Public
Joined: Dec 2004
Posts: 1,512
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From: Northern Virginia near DC
If you haven't done it yet, there is a DIY for an easy mod to help your A/C: https://www.rx8club.com/series-i-do-yourself-forum-73/diy-easy-mod-colder-ac-42322/. The FYI mentions using a specific type of heat tape, but foam pipe insulation from the hardware store works fine too -- and it's something like $2 for a 6-foot section.
I had the same problem, my RX8 would never cool down on really hot sunny days. Tint your windows, it helps. I got 5% on the rear, and 35% on the sides, I noticed my 8 cools off a hell of alot quicker now. And I havent been pulled over yet. Thats my advise.
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Joined: Jul 2006
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From: New Orleans, LA - formerly El Segundo, CA
My 07 works pretty good as long as the car is moving. When it is at an idle, it doesn't work that well, particularly on a hot day. I like to open the windows and sunroof to let all of the superheated air out 1st.
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From: In the hills between San Miguel and Parkfield - "up in the boonie lands", Central Coast of California, Wine Country
Works OK - temps up to 107
Just have to know that you turn the fan on, then push AC
Works best when the mode button is set to the arrow in your face
about half power when arrow is both face and feet
If you are still hot close the drivers side window
When you first get into the car and its over 98, open the side windows and roof for a moment to let the heat out
Everything is cooler if you park in the shade or have a cover
It is stupid to run a car (any car) during Noon to 4 on super hot days and don't fill the tank until things cool down - better economy and you won't set stuff on fire! Heat is an engines enemy and evaporation can only cool an engine a limited amount on a super hot day (temps 103-120 F)
Just have to know that you turn the fan on, then push AC
Works best when the mode button is set to the arrow in your face
about half power when arrow is both face and feet
If you are still hot close the drivers side window
When you first get into the car and its over 98, open the side windows and roof for a moment to let the heat out
Everything is cooler if you park in the shade or have a cover
It is stupid to run a car (any car) during Noon to 4 on super hot days and don't fill the tank until things cool down - better economy and you won't set stuff on fire! Heat is an engines enemy and evaporation can only cool an engine a limited amount on a super hot day (temps 103-120 F)
my previous car, a chrysler lebaron, had a better ac than my 8. but the 8s ac is still more than adequate. i dont complain.
at least the 8 has heat. which the lebaron did not. :P how can a car.. which has an engine that produces heat... not have heat? i just dont get it.
at least the 8 has heat. which the lebaron did not. :P how can a car.. which has an engine that produces heat... not have heat? i just dont get it.
I zoom therefore I am.
Joined: Mar 2007
Posts: 4,919
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From: San Jose, CA
I start work at 6am so never an issue with heat in the morning. Windows are tinited and I use a sun shade with the sun roof vent open while I'm earning money for the 8. When I leave work, 2 mins on the road and it's cool as a clam.
PaPa Bear
Joined: Sep 2006
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From: Miami, Florida
I live and commute in South Florida. You can be in 90 deg weather sitting in a line of traffic for some time. My 2004 A/C works great.
Registered User
Joined: Jun 2007
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From: London/Toronto, ON, Canada
Hottest day that I've driven it so-far, 99F. Air conditioner worked perfectly well, I never set the fan higher than the second setting; good enough for a severe case of RT.
My other car, a '91 Explorer, takes 15 minutes to completely cool-down that cavernous interior. The 8 is a meat locker in comparison. No complaints.
My other car, a '91 Explorer, takes 15 minutes to completely cool-down that cavernous interior. The 8 is a meat locker in comparison. No complaints.