Car is a 05 gsr with 107k

Within the last week the a/c system intermediately starts blowing warm air, seems to occur after driving for a while and will come back to blowing cold and then warm again. At times when the car blows warm condenser fans are still operational but the clutch is disengaged. I check the low side pressure and it was a tad low and I added a bit of refrigerant and it sits at between 40-45 or so right now with the clutch engaged and still has intermittent problems with the clutch disengaging. I haven't had alot of time to troubleshoot yet but at a time when it wasn't working the clutch relay had constant power and the switched 12V power. When I plugged the relay back in it began working again. I'm leaning towards the relay going bad or the a/c clutch itself. Anyone had a similar problem? Are there any known components or switches that tend to fail on these cars at around 100k mark. Any help is appreciated.

 

i'm a diesel mechanic on big rigs but have gone to the thermo king school for refrigeration cause i work on a/c systems on trucks and trailors..... from the way it sounds... since it is kicking on and off your going to have to check power right at the compressor. obviously your going to want to check when it kicks off. if you have power and the clutch isn't engaging then your compressor is shot. another thing is refrigerant psi's low and high are based on the temperature outside (ambient). it could also just be cycling alot. with you guages on mainly your high side watch yor pressure. as the compressor is on it will rise the pressure. it will go up then kick off. at that point your engine fan should kick on and the pressure should go back down and will keep doing this over and over.

 

any questions p/m me

 

I have a 05 RA, last week I spend $500 on a new air compressor and hose, I had the same problems as you and also my car is over 100k you should chek your compressor you will have to change it soon!!

 

Yup had this problem in my evo 8. Compressor has 3 parts that can be purchase separately and it was the coil area. After about 20-30 min of use the coil got hot enough and separates just enough so once the ac clutch cycle's off it never turns back on. After it cools works again then same cycle starts. Well that what the AC dude said anyways but my problem was fix still working 2 years later. Good luck.

 

I had this same problem. My friend said something about a relay. He fixed it for me for free, said it was an easy fix. I can ask him more in depth if you need me too :-)

 

I have an evo 8 that just turned over 100K the other day and I'm experiencing the same issues as sud0u. It worked today for the first 20min until I punched it up a hill... never came back until 20min later or so. I didn't leave it on blowing hot air for 20min, but it was about that long until I got it to kick back on. When it did come back it only lasted a few minutes. I need to get this fixed seeing as it was 90 today!!!

I'd like to hear more on the coil or relay that was mentioned.

Not sure if it matters but I just recently installed an fp Green and full exhaust. Left the heat shields off (top and bottom) and was wondering it that is overheating something maybe? Also... my buddy put in the turbo timer at the same time and mentioned he may have left a bolt out that may have been grounding something (don't get me started on that!!!).

I was really just looking for the solution part of this thread but it seems to have died anyway... I'd appreciate any help.

 

OK well I fixed my problem. The problem was that the compressor clutch armature and hub were worn and the air gap between them was more than factory spec by a good bit and the coil wasn't able to pull them together to engage the compressor.

On the compressor there is a shim between the outer armature and the rotating hub that it must engage with. As the two pieces wear overtime this gap increases and eventually the coil can't engage them. The dealer sells different sized shims and they can be replaced. For mine I took apart a spare compressor and used the thinnest shim which brought the clearance to the tight side of factory spec. AC works great again and the only part I needed to fix it was a $0.02 shim/washer. Would have been pissed if I spent $600 and found this out later, lol. Once this wears out again I'll just go ahead and replace the whole compressor clutch assembly but I was too lazy this time.

Just a heads up for anyone with a similar problem, the factory service manual has the diagram and clearances. This can be changed without even removing the belt.

 

^^^ That's good to know. I had read elsewhere on here that the clutches were an issue. Maybe a shim was all the other parties needed too.

 

I think so. Eventually the wear items will need to be replaced and they are a total of about $130 retail at the dealer, The whole assembly with magnet is about $230 and can be replaced while the ac compressor is on the car without discharging the system. Only special tools needed are snap ring pliers and a set of feeler gauges.

 

Do you think the shim replacement could address my A/C problem too? Here are my symptoms:

My A/C works fine most of the time. However on four recent occasions when I took my car to the track, the A/C stops blowing cold and only blows hot after I have completed 2 sessions on the track. (I was not using the A/C while driving on the track, I was just trying to use it when I went to fill up the tank between sessions.) Eventually, anywhere from 2 to 12 hours after the track day is over, the A/C will return and work again.

Thanks!

 

Ok so I went to run to the store, then lunch, then target. My ac has always worked fine, until today after all running around was done I started my car, no ac. How can I check the compressor clutch?

 

https://www.evolutionm.net/forums/ev...ng-advice.html

 

This seems to be a very common problem, as I have the same issue.... blows hot.. than cold... than hot... than cold, never consistent.

 

My ac blows ice cold all the time but occasionally when it's been on for awhile white cloudy air starts to blow out of the center vent. I thought inwas being gassed the first time I saw it. Any ideas?