AC operating intermittently, any idea what the issue could be?

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Jan 14, 2017
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The other thread about my uncles subie was highjacked by yours truly and died an honorable death. I have decided to make a new thread in regards to my personal vehicle.

The car is a 2012 Honda Civic LX. AC didn't work until I tinkered with fuses. Now the ac blows nice a hard, but it's not quite as cold as I'd like it. In fact, it starts out warm on a cold start and gets colder the longer I drive. Talked with a Honda parts person at my job tonight and he suggested the condenser is experiencing issues. I'm also looking at the possibility of low freon.

And just for good measure I checked the fans and they work properly.
 
But, for the home DIYer, check the condenser(in from of the radiator) for debris such as dust, cotton and yuk!
Then have it tested properly with a set of manifold gauges
 
After being parked in the sun for a while, the interior of any car becomes dang hot. The dash, airbox and associated ductwork can take a while to cool down. Perhaps there is nothing wrong with the AC system. You can buy a cheap meat thermometer at the dollar store and place it in one of the vents. If it drops down into the 40's after a few minutes I don't think the AC can be improved.
 
My Genesis Coupe with a black interior if driving facing the sun has a had time making it cold. Air still comes out the vents at 40F with max fan speed. When it's a cooled down it runs off the evap temp and cycles at 36F-38F.

I had a Taurus that the AC would quit working when driving on the highway but when I came to a stop and turned it back on it would work. Turned out to be the clutch was worn and removing the shim made it work great.
 
You cant diagnose a problem until you are 100% positive it has a proper charge. That means sucking it all out,vacuum then charge with a scale.

Not a can with only a low side gauge and not just sticking guages on it.
I'm having this done tomorrow. Evacuation and recharge.
 
Just took a picture of the condenser. Looks to have a lot of debris in it.

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It's going to require some troubleshooting. Vacuum and recharge will eliminate that variable, so that's good.

I had intermittent A/C on my Ranger when the low pressure switch started going bad. Also clutch gap can cause intermittent A/C.

If your A/C goes from zero to good by fiddling with a fuse, that sounds like it could be electrical. IME, refrigerant level issues are not really intermittent, it's more like you have generally poor A/C operation that under some conditions will be provide acceptable performance and under other conditions will be unbearable.
 
Our smart car in extremes will rachet air down to almost off until the stress is reduced, on a very hot day , at high speed the air goes away.
Slowing down restores it.
 
Based upon the info you have posted so far in both threads, it is highly likely that the Civic is low on R-134a refrigerant. However, that means there is a slow leak somewhere that allowed the refrigerant to escape. Your Civic's compressor clutch air gap may also be excessive and requires adjustment.

Like other BITOG members stated, you need a professional to diagnose and repair the potential leak or component malfunction before performing the evacuation and recharge procedure. Hopefully the shop you have the appointment with will pinpoint and resolve the root cause of the problem.
 
I would start with the low hanging fruit:
1. Clean the condenser
2. Clean the evaporator
3. Replace the cabin air filter
After those, you can get involved in the internal workings of the AC pressure system.
 
I would start with the low hanging fruit:
1. Clean the condenser
2. Clean the evaporator
3. Replace the cabin air filter
After those, you can get involved in the internal workings of the AC pressure system.
I agree. Start with the things that are free/cheap DIY and need to be done anyway.
 
The shop my aunt told to me to go to is amazing. State inspection and AC recharge for under $200.

They said the system had .4 lbs of freon and it holds 1lb. They evacuated the system, added 1lb and put two cans of dye in it and said if the ac gets warm again to swing it by and they'll check for leaks.
 
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Easy work - get a can of foaming coil cleaner from Home Depot, probably in the aisle selling ducts, vents and thermostats for home air conditioners. Saturate the condenser with the stuff and let it foam out for 5 minutes. Spray it off with a garden hose. This does not save the world, but when checking amp draws with pressure gauges on household AC, it’s easily worth 10%.
 
The late 90s Taurus and Sable the condenser would clog up with fuzz. After a while only the area where the fans actually mounted was getting air drawn through.
 
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