AC Issues Persisting

[mLuMaN83]

So I finally brought my car in for this crazy AC issue I am having. It was a pound low so they filled it up and I coughed up $119. Ice cold out both vents. Working fantastic!

Then while on the highway... BAM! Warm air through all vents! GAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!!!!!!!!!!!!!!!! !!!!!!!

So here we are.

- AC is charged and ice cold out all vents when working.

- Stops blowing cold at random and blows warm through all vents. I turned the system off for awhile while driving, hit auto to turn in on again, and whammo... ice cold and functioning correctly.


- When blowing warm, and I change the setting from face-feet-etc, as the flaps make their change to blow to the location, I feel a quick burst of cold air as the flaps switch, then warm again. This must mean that cold air is blowing somewhere but not where it is intended.

- Control unit replaced

Is this a flap/door issue? I don't know what else to do here...

[Hornung418]

Sounds like you don't know how to properly use the auto function...search e46F for the solution.

Sent from my GS3.

[mLuMaN83]

Sounds like you don't know how to properly use the auto function...search e46F for the solution.

Sent from my GS3.

I absolutely do. Auto, manual, doesn't matter. When it goes warm, it stays warm on any setting until I shut the system off for awhile and restart the system.



I am thinking I may have found the culprit. Blower motor resistor. At first, I wouldn't believe that this part could be responsible for blowing hot air when the AC in on but it turns out that this is one of the symptoms! I am going to buy one, put it in, and see what happens. I think this may be it...

EDIT: Not sure FSR is the problem... reading more.

I'm running out of options here... maybe a heater control valve. This is ridiculous because I can't find anything that discusses my exact issue.

[pilotnick1203]

I absolutely do. Auto, manual, doesn't matter. When it goes warm, it stays warm on any setting until I shut the system off for awhile and restart the system.



I am thinking I may have found the culprit. Blower motor resistor. At first, I wouldn't believe that this part could be responsible for blowing hot air when the AC in on but it turns out that this is one of the symptoms! I am going to buy one, put it in, and see what happens. I think this may be it...

EDIT: Not sure FSR is the problem... reading more.

I'm running out of options here... maybe a heater control valve. This is ridiculous because I can't find anything that discusses my exact issue.

Odd, were you driving it hard, I was out on the track and all of a sudden mine started blowing warm air, normal driving it was fine. I'd go under the cowling and take a peek at the blower motor and that area, it's an easy job.


Sent from my iPhone using Tapatalk

[llll1l1ll]

Just a thought: maybe the dial that controls the flow of hot and cold air through the upper vents is busted? Or maybe in the hot position? Otherwise, it sounds like your flaps are on the fritz.

[mLuMaN83]

Dial on vents is fine. It happens randomly. No hard driving required.

I have narrowed it down to 2 things at this point. Some sort of flapper door actuator or the HCV. I am going to try to replace the HCV and see if that fixes the issue. After A LOT of reading about the HCV, I have many of the symptoms for a malfunctioning HCV. It fixed some of the peoples problems and others not. We will just have to see. If not, it must be some sort of flapper door malfunction. I hope it's not a door. That means ripping apart the dash and I am not looking forward to that at all.

[mLuMaN83]

I wanted to give an update on this situation.

I have managed to narrow down the issue but not the fix. When the AC goes warm, I can manage to fix the issue by just adjusting the temperature up to 91 degrees for a second and then back down to 70, where I like it, and the AC comes right back cold until she goes warm again. Another issue that has popped up is a coolant light which seems to be RPM sensitive. It also "at times" seems to light up and the AC goes warm right after the light. Not sure if the issues are related but I have a feeling they may be.

No overheating issues. Cooling system seems to be 100% although I have not yet checked for bubbles in the system. After the overhaul, I had zero issues for a long time until recently.

[ClimRox]

Did you end up replacing the HCV?

[mLuMaN83]

I looked around awhile back and didn't think that that was the issue. It may be now that I've narrowed it down to what makes the AC blow cold again after it goes warm. Just simply jacking the temp up quickly then back down gets me back to cold ac. When getting the heat going, there is a change in something that allows the cold to return fully. Reason I didn't initially think it was the HCV is because I do in fact have heat.

I may try replacing the HCV with a used cheap one and see if it stops the issue. This could be a flapper door issue as well but I'm starting to think not because it seems to correspond with this coolant light as well. All kinds of weirdness going on here.

[zYx]

Can you reproduce the problem in idle/not moving?
If yes, you can see if the compressor clutch is disengaging so you can rule out flaps if it stops spinning.