A/C on cool air blowing then blasted with HOT AIR...HELP!!!
 

I have a 2004 RX-8...for the past 22 months I have really enjoyed my car. She's almost 2 years old now and all of a sudden I'm having unacceptable problems.

First and FOREMOST...the A/C
I live in SUNNY HOT HOT FLORIDA...therefore A/C is REQUIRED for survival!!!
My A/C runs really really cool...then something happens and it starts blasting HOT air (right off the engine it seems). The dealer told me it car is designed to automatically shut off the a/c...blah blah blah. I suppose since I'm FEMALE they think I'm STOOPID!

I first noticed the problem when travelling at high speeds then downshifting to slow down. But now it happens arbitarily at anytime. I can't take it anymore.

I LOVE MY 8. Don't want to get rid of JSCJANE...but I'm almost 2 years into a car purchased brand new and having problems...NOT A GOOD SIGN. Especially for someone like me who likes to KEEP her mazdas until the wheels fall off.

Oh...did I mention the driver side visor snapped today at the base?!! UUUGGHHH!!! :banghead:

above 6000 rpm i believe the ac shuts off, so downshifting at high speeds will cause that to happen. also make sure the air is internally circulating and not drawing outside air then trying to cool it (that bottom button on the climate control interface)

The 2004's also have an issue with the AC Amplifier. A ->TSB<- has been released in regards to the problem.

Check your VIN to see if it's on the list, if it is, then go for a replacement!

dillsrotary is right too, if you're downshifting at high speeds, the ECU can turn off the AC so you don't destroy the compressor.

i was having the same problem with my 2004. just got it back from the dealer with the new amplifier installed and everything seems to be working fine. i havent tried it in extreme heat yet (and probably won't since fall's almost here).

Thanks for the information regarding the AC Amplifier. I will cross reference my VIN number against the list.

FYI... my statement about high speed driving and downshifting may have been a little misleading...not that drastic! I was pissed when i posted my message yesterday.

THANKS AGAIN!!!

Do the wrap with heat resistant mterial.

See the DIY section.

Get The A/c Amplifier Replace(tsb). I Got Mine Replace 5 Month Ago And Its Working Great Now.

Not sure if this applies to your vehicle, but can't hurt to try. It did wonders for mine(Mine is a Jan 2004 build)




AC NOT COOL (AFTER 9/11/03 PRODUCTION)
Applicable Models
Model Starting S/N Ending S/N
2004 RX8 40118171 ********

Some customers may complain of lack of AC cooling from the vents. This may be caused by the intake air selector (recirculate / fresh) in the "FRESH" mode. Cooling the interior of the vehicle may take longerif the air intake selector is in the "FRESH" mode. Maximum cooling is acheived when the intake air selector mode is in the "RECIRC" position. The AC amplifier can be programmed to automatically default to "RECIRC" mode when the following conditions are met: 1. Ambient air temperature is 68 deg. F or higher. 2. HVAC control mode is in "FACE" mode. 3. HVAC temperature is in maximum cool setting. Customers with this concern should have their vehicle repaired using the repair procedure. NOTE: Vehicles produced before 9/11/2003 are not programmable N should have the AC amp replaced per Service Bulletin # 07-002/04 1. Verify concern. 2. Verify ignition switch is in OFF position. 3. Press and hold the front defrost and air intake selector buttons simultaneously. 4. Turn the ignition key to the "ACCY" position for 3 seconds. (Continue to hold the buttons down from step #3.) 5. Turn the ignition key to the "ON" position for 3 seconds. (Continue to hold the buttons down from step #4.) 6. Successful programming will be confirmed by the rear defrost indicator light flashing 3 times. NOTE: If vehicle's battery dies or cables are removed, the programming will not be retained and must be performed again.

A/C Problem
 

My A/C switches from cold to blowing hot air with temp knob set to cold. if i rotate it to hot then it starts blowing cold air. i also had a problem when it was cold outside when the temp knob was set to hot it blew cold air. i took it to the dealer and they said that they could not duplicate this but they did notice a fluctuation with tha A/C. they said for $60 they would test the freon level. and if it turned out to be a bad component they would replace it. i told them that no way could it be the freon when the problem is on the control side. it blows cold air but with the temp knob in the wrong position and vice versa with the heat. ive checked the service bulletin and my car is a jan 04 build but is not within the vin range but it has all the symptoms for replacing the A/C amplifier. the tsb says nothing about charging $ to check the system. it says to verify customer concern and swap the Amp. they stated there was a fluctuation but could not get the problem with the knob to duplicate. shouldnt they have replaced the amplifier once they verified the flux?

My Rx8 will be blowing cold air then suddenly start blowing hot.
It does this in recirc and fresh mode as well as when the ac is on or off.
RPM are low or high. RPM doesn't seem to change the result.
The compressor does kick on and the amplifier re programming didn't do anything. Rad appears fine.

I saw it blip from 0-2 then it will jump up to 10-13 for a few minutes and back to 0-2.
I noticed it start when it was hot out (30 C) so thought it could just be the weather but it was only 10 C the other day and still blew hot air. Hotter than the temperature outside.

Any ideas?

yeap your ac control board is bad. That's why it just jumps. it's an easy fix to pull the board and solder 3 connections on the know that determines the temp. or a few hundred dollars to buy a new one that will fail again.