Common A/C issues?

[heyybaker]

I was tempted to put this in the engine category, but I'm really not sure where this belongs. Anywho, my A/C isn't blowing cold. It may just be that it needs refrigerant, I'm going to try this first. If I'm unlucky and this isn't the case, what are some common issues with A/C in Neons that I should investigate.. maybe things that have been known to break a lot? At least I'll have somewhere to start at that point.. then again.. may be lucky and it just needs refrigerant.

[ThatKevin]

is the compressor coming on?

If it is then maybe you have a leak, hopefully it'd be small and you can just refill it.

[NyNeon0813]

Yea def try the refrigerant first. Mine had a crack in the ac condenser so the refrigerant would spray out

[ThatKevin]

Yea def try the refrigerant first. Mine had a crack in the ac condenser so the refrigerant would spray out

well see if the compressor comes on.. if not then no need to waste $$ on a refill

[Danteneon]

I was tempted to put this in the engine category, but I'm really not sure where this belongs.

That's OK. I never know where to put A/C questions either. Since it is focusing on the underhood bits, let's say engine.

[heyybaker]

Hey all, when I arrived to WalMart, I parked in the back of the parkinglot, left my car on, and opened the hood. I've never seen the compressor before, but my dad described it perfectly and I found the little wheel that spins from the belt. He said if the middle of the wheel isn't spinning when the A/C is turned on, the compressor is broken. Assuming he's accurate, my compressor IS working.. when the A/C was off, it wasn't moving, I turned it on, went back over, and the middle was spinning as well.

SO.. I bought refrigerant.. with leak sealer (which I realize isn't going to fix any big leak if there is one).. but it also has dye so we can more easily find the leak if it's big enough to need immediate attention.

[boostalot717]

Yes your compressor is working and that also means that the pressure switch is also working. Also just a heads up refrigerant does not go bad. The only reason it needs replaced is because of a leak. You should be checking vent temp vs. ambient temp to help determine whats wrong. Did you a/c work last summer? Many early spring a/c problems come can be fixed by simply cleaning out the evaporater. Also you really should be checking high and low side pressures before adding refrigerant, as to much refrigerant is more harmful to a/c compents than none at all.

[heyybaker]

Well I just bought the car in February :p and of course it seemed to be blowing cold air then.. because it was cold outside. So I have no clue to if it has been working or not. I guess I will find out. We will look for leaks definitely..

[heyybaker]

So, we got an air conditioning pressure gauge, and it was definitely empty so we added the UV dye refrigerant. Cold air for a few minutes, and then we saw smoke pluming out from under the hood.. must be a leak. But, we couldn't find any dye ANYWHERE.. useless refrigerant . However, with a flashlight, we found a gash in the low pressure a/c hose.. the steel/metal part of it. We think it's leaking there.. otherwise, maybe a seal..

When I turn the A/C on, I notice inside of the car, through the vents.. I hear hissing noise. It hisses, then stops, and continues this so long as I have the A/C on but NOT the heat. It goes: HISSSSSSS, stop for 2 seconds, HISSSSSSSS, stop for 2 seconds.. it's really weird :/ Any ideas?

[boostalot717]

Ok heres a few observations on this. First if high and low side contained no pressure before you added refrigerant then you pressure switch is bad. As it should not allow the compressor to run. Next the dye requires a black light to be seen. Hence UV dye, you may see it in large puddles but fine mist you won't.

Now the hissing sounds through the vents. My guess is a refrigerant leak either at the condensor under the dash or at the H-block/TXV. If its definatley heard through the vents then that can rule out the txv. And I am willing to bet that the hiss is when the compressor clutch engages and disengages.

Just some FYI when you replace parts on a A/C system or anytime there is a leak once the repair had been made and tested the system must be put in a vaccum. You CAN NOT just add refrigerant and go.

[occasional demons]

Also leak sealer is generally a bad idea. Depending if the leak is on the low side or the high, it can plug the system.


Like boostalot717 said, it really should be evacuated to get the moisture out.

The hissing may be a normal sound. mine has made a "hissing" noise when shut off for as long as I've owned it. It may just be the refrigerant pressure escaping through the valve.

A/C is really one of those things that should be left to a reputable shop, because in the long run it will cost you less.

Unless you have a vacuum pump to evac the system, you are only inviting failure by recharging it yourself.

[heyybaker]

Also leak sealer is generally a bad idea. Depending if the leak is on the low side or the high, it can plug the system.


Like boostalot717 said, it really should be evacuated to get the moisture out.

The hissing may be a normal sound. mine has made a "hissing" noise when shut off for as long as I've owned it. It may just be the refrigerant pressure escaping through the valve.

A/C is really one of those things that should be left to a reputable shop, because in the long run it will cost you less.

Unless you have a vacuum pump to evac the system, you are only inviting failure by recharging it yourself.

*sigh* You're right.. as much as we'd like to think we can do anything ourselves, we don't know much about A/C. We DO have an Uncle Ray (well, for my dad, cousin Ray?) who has been working on car air conditioning systems for a LONG time, he's very knowledgeable in them and definitely has all the proper tools needed to diagnose/fix. But he lives up in Cumberland, or something, so it's at least an hour drive.. in the heat XD. Oh, the irony..