Subaru Outback Forums banner
  • Hey everyone! Enter your ride HERE to be a part of this month's Outback of the Month Challenge!
1 - 9 of 9 Posts

·
Registered
2001 Outback LL Bean
Joined
·
4 Posts
Discussion Starter · #1 ·
First, I will apologize if this has been asked and answered. I looked around and saw plenty of AC questions but not this one exactly, though I may have missed it.

Secondly, while I do most of the minor work (replaced alternator,power steering pump, etc.) on my car myself, I am unfamiliar with some terms so please bear with me if I ask stupid questions.

I live in SW Florida so it's just shy of a billion degrees out right now. Usually the AC has been fine. Not super cold, but no actual problems either. Until the other day. It wasn't as cold as I remember so I picked up a can of freon with the gauge and added the freon. The gauge shows that it's better, but still low (Not inside that "V" range on the gauge, but still in the "Filled" section.)

Fast forward a couple days and I notice that when the car is moving, it's blowing cold, but once I am idling, like at a red light or in traffic, it blows lukewarm at BEST.

Another note that may or may not have anything to do with this issue:
-Twice within the last 3 weeks I have shut the car off only to have the fans keep running. The first time I figured they would shut off once the engine cooled down but 10 minutes later, they were still running. I pulled the main fan relay and put it back in and the fans shut off.

In the research that I've done so far I've read that it could be the condenser fan going bad and not blowing, or it could be a bad relay. I am planning on picking up new relays tonight and see if that does the trick. Better to start out with the cheapest fix and work my way up.

Thoughts? Ideas? Suggestions? Experiences? All are welcome. Thank you so much for any help!
 

·
Premium Member
(formerly) 03 H6 OBW , (presently) 06 WRX Sportwagon & 2021 Honda CR-V
Joined
·
18,406 Posts
good troubleshooting I'd say.

good chance the relay or contacts to it are becoming intermittent.

worst thing that happens is, you eliminate one possibility and get a 16 year newer relay!
 

·
Registered
2001 Outback LL Bean
Joined
·
4 Posts
Discussion Starter · #3 ·
Another thing I will check out when I get out of work today is to see if the clutch is engaging.

If it isn't, is the recommended course of action to replace the clutch or the whole condenser?
 

·
Registered
2001 VDC Wagon - White pearl - 302,000 km
Joined
·
466 Posts
Start with the relays, but please keep in mind that the AC system will not perform the same way when it's 80 outside, and when it's 95 outside. AC compressors will age, just like an engine will, and they will gradually lose performance at lower rpms. At idle, the fans can only pull so much air through the condenser to cool it. If it's 95 degrees, and humid, and you are sitting in traffic, and your blower is on high, etc...these will all lead to poor performance at idle. Once you bring up the rpms, the compressor can move a higher volume of refrigerant through the system, whereby increasing the cooling effect. Everyone's simple answer to an AC system that is not cold on a hot day, is that it must need a can of refrigerant. Can you elaborate on what you mean by "The gauge shows that it's better, but still low". What pressures are you seeing? Can you take a picture?
 

·
Premium Member
(formerly) 03 H6 OBW , (presently) 06 WRX Sportwagon & 2021 Honda CR-V
Joined
·
18,406 Posts
recently I have read of folks taking shims out of the clutch to further guarantee engagement. But it doesn't seem to me that your issue is related to that - maybe some general electrical or charging issue might cause the relay to drop out...???

anyway, are you observing the clutch cycle too much? there is a 'rev sensor' in those compressors that might be in this mix - try more specific searches as I have little experience , just changing worn o-rings and charging.
 

·
Registered
2001 Outback LL Bean
Joined
·
4 Posts
Discussion Starter · #6 ·
Start with the relays, but please keep in mind that the AC system will not perform the same way when it's 80 outside, and when it's 95 outside. AC compressors will age, just like an engine will, and they will gradually lose performance at lower rpms. At idle, the fans can only pull so much air through the condenser to cool it. If it's 95 degrees, and humid, and you are sitting in traffic, and your blower is on high, etc...these will all lead to poor performance at idle. Once you bring up the rpms, the compressor can move a higher volume of refrigerant through the system, whereby increasing the cooling effect. Everyone's simple answer to an AC system that is not cold on a hot day, is that it must need a can of refrigerant. Can you elaborate on what you mean by "The gauge shows that it's better, but still low". What pressures are you seeing? Can you take a picture?
I will try to take a pic tonight. I believe the pressure was around 35. I just used one of those gauges that come with the refill canister.
 

·
Registered
2001 Outback LL Bean
Joined
·
4 Posts
Discussion Starter · #7 ·
recently I have read of folks taking shims out of the clutch to further guarantee engagement. But it doesn't seem to me that your issue is related to that - maybe some general electrical or charging issue might cause the relay to drop out...???

anyway, are you observing the clutch cycle too much? there is a 'rev sensor' in those compressors that might be in this mix - try more specific searches as I have little experience , just changing worn o-rings and charging.
I have seen that as well. When I get out of work I will see if the clutch is spinning while the car is still parked but running.

As far as the second part of your post, I don't know what a 'rev sensor'.
 

·
Registered
2001 VDC Wagon - White pearl - 302,000 km
Joined
·
466 Posts
I have seen that as well. When I get out of work I will see if the clutch is spinning while the car is still parked but running.

As far as the second part of your post, I don't know what a 'rev sensor'.
The rev sensor is a speed sensor that is incorporated in the AC compressor. It is native to the H6 only in 2nd generation Outbacks, and here's why: The H4 has a separate belt driving the compressor, so if the compressor seizes, or the belt breaks, it's not detrimental to the rest of the engine..ie, it will still function safely.

The H6, having a lone drive belt cannot afford a seized or slipping compressor, so a rev sensor is needed to let the ECM know if the drive belt is rotating the compressor at a proper speed. The rev sensor is compared directly to the crankshaft position sensor, as the pulley diameters are basically exact. I believe a 15% deviation will disable all AC clutch operation, until the engine is turned off and restarted. This scenario is usually a tell tale sign that the clutch air gap is getting too large, because the clutch will start to slip when the gap gets too large. Typically, pulling out a shim will be enough to restore normal operation.

I don't recommend this, but my H6 had this very problem, and for a few days, I found myself popping my car into neutral, on a straight road, turning off the engine, then restarting it, to restore my AC for another few miles. Now, while I don't doubt that California and Florida can get some high temperatures, there's something about the humidity of the freshwater great lakes, that can amplify a heat index to the extreme. I happen to be sandwiched between lakes Erie and Ontario, in the Niagara peninsula, so there's no escaping the frequent summer heatwaves that occur. For this reason alone, is why I carried out the "neutral reset" procedure. It can be used as a diagnostic tool, but only if it is absolutely safe to do so.
 

·
Registered
OBW H6 VDC, Tribeca, XT6
Joined
·
12,385 Posts
Low on refrigerant? I guess that ignores the fans.

Get a hose with pressure gauge so you can check and make sure you're not overcharging. Add a little refrigerant - ideally wait for a day when it stops during idle and add it then - if it then fires right up you know it was low.
 
1 - 9 of 9 Posts
Top