A/C Air Conditioning Diagnosis Help

[ymehuuh]

Hi,

I searched the forums and could not find a general solution to my problem. My A/C on my 1998 eclipse GS has been blowing normal air for quite awhile. I had thought I was empty on refrigerant so I paid $100 to refill it. The guy then told me my refrigerant is full and it is holding pressure but my A/C won't blow cold. He said he'd charge $100 for a diagnosis. I wanted to exhaust all my options before having to go to a mechanic.

What is the typical troubleshooting for when air conditioning doesn't work?

 

[Rob10_99]

Let the system run, and one set of pipes should be hot, while the other are ice cold.
I assume all of your pipes are hot, and there is a clog in the system.
Hot going to radiator in front, cold going back.

You sure your ac clutch is coming on?

 

[ymehuuh]

I'll go run my a/c in a few minutes and see if any pipes are hot or cold. How do I check my a/c clutch?

 

[ymehuuh]

I just checked both the pipes and they are equally scorching hot. So if there is a clog/blockage how would I go about clearing it?

 

[Rob10_99]

The only real way to get it clean is replacing parts, ac system should have no particulate in it.
I would suggest using an air hose to see what flows and what doesn't. You will have to get the system evacuated though, theres over a pound of R12/134a in there, see if the shop that charged it will take it back in return for more when you replace parts that are clogged.

btw, whatever you do, dont have it converted, R12 is way better!
If your shop doesn't fill with it, find a shop that will.

 

[96mitsugsx]

The freon for the car is already 134A. It would be stupid to convert it to R12. Plus, R12 is bad for the ozone layer and a lot more expensive than 134A. If your refrigerant was full he shouldn't have filled it more. To check if your clutch is kicking you should look at the middle part of the compressor if turns when you swith on your a/c. If both lines are hot, there might be moisture in the system. Evacuate the system after replacing your receiver/dryer, expansion valve and dont forget to clean your evaporator and condenser. Just make sure that your compressor is still good. You can tell that if you have a manifold gauge. If the high side is high then your compressor is going bad. If you do not have the right tools for the job just pay someone competent to do it for you.

 

[Rob10_99]

If theres a clog, where did it come from? the only real moving part in the system is the pump.
Cleaning is purely to get it working, not a real fix.

R12 is that much better.

 

[96mitsugsx]

You will always get dirt in the system. There is no way to prevent it but you minimize it by always making your interior clean by vacuuming. R12 is old school freon and a lot of technicians do not recommend retro fitting a 134A system to R12.

 

[Jeff99GS]

Dude the Refrigerant is in a SEALED system the interior DIRT does NOT get in the system ever...It is ALL under Pressure. If your cooling system is FULL then don't mess with the compressor or any of that...Im almost 99.999% positive you DO NOT have a Clog in the refrigerant system.... It is Most likely an electrical problem...check the AC fuse and the Relays under the hood. have someone turn the air on and off and listen or feel the relays they should click when you turn the air on.
The relays are In the Fuse box under the hood...look on the fuse box cover for the location of the AC Relay's and Fuses...there is more than one relay I believe

Check all the plugs to the cooling system...there is a silver can up in the front fender area...if that came unplugged the system will not work.

Check the clutch on the compressor...you have to watch the AC compressor while someone turns the AC on and OFF ...the pully on the AC comp will sort of click and move inward a little....That means It is working properly...If it does not click then the clutch is NOT activating the Comp

Is your second Fan coming on to cool the condensor coil and Radiator?

Does the AC switch in the car work? it should light up green when in AC mode

 

[Defiant]

Your air conditioning control unit has died. They are no longer available.

 

[ymehuuh]

Dude the Refrigerant is in a SEALED system the interior DIRT does NOT get in the system ever...It is ALL under Pressure. If your cooling system is FULL then don't mess with the compressor or any of that...Im almost 99.999% positive you DO NOT have a Clog in the refrigerant system.... It is Most likely an electrical problem...check the AC fuse and the Relays under the hood. have someone turn the air on and off and listen or feel the relays they should click when you turn the air on.
The relays are In the Fuse box under the hood...look on the fuse box cover for the location of the AC Relay's and Fuses...there is more than one relay I believe

Check all the plugs to the cooling system...there is a silver can up in the front fender area...if that came unplugged the system will not work.

Check the clutch on the compressor...you have to watch the AC compressor while someone turns the AC on and OFF ...the pully on the AC comp will sort of click and move inward a little....That means It is working properly...If it does not click then the clutch is NOT activating the Comp

Is your second Fan coming on to cool the condensor coil and Radiator?

Does the AC switch in the car work? it should light up green when in AC mode

I'm sure the person who worked on my car filled it with 134a. I will go through this troubleshoot method before taking anything apart since my refrigerant is full right now. The green light does come on when I push the A/C button and I hear something come on from inside my car. I can also tell my engine has to work a little harder at idle. I'll have to grab another person later to check the A/C clutch and compressor. Before that I'll check all the fuses again.

Thanks!

 

[96mitsugsx]

You probably haven't seen a clogged expansion valve. I have. Do you also know what an orifice tube is in domestics? Keeping your interior clean helps yourevaporator to be clean also.

 

[theSicKness]

I'm sure the person who worked on my car filled it with 134a. I will go through this troubleshoot method before taking anything apart since my refrigerant is full right now. The green light does come on when I push the A/C button and I hear something come on from inside my car. I can also tell my engine has to work a little harder at idle. I'll have to grab another person later to check the A/C clutch and compressor. Before that I'll check all the fuses again.

Thanks!

Im Fairly Sure Being a 98 it didnt come with R-12, One if it does have R-12 Retrofit it im sure it doesnt though.. R-12 Is extremely expensive.
1. you system may be full but if its contaiminated with air then it could be your problem only way to fix it is to remove all the 134-a and pull a vacuum on the system for at least 10 mins.
2. Your compresser is dead its not cycling on and off.. its not doing its job of cycling the 134A to a hi-pressure.
3. or your pressure switch is dead not letting the compresser to switch on and off..


its very easy to tell take it to a mechanic and let him hook a set of hi-low pressure gauges to it.. should only take him a min to tell..


Jesse

 

[Defiant]

It's not the usual AC diagnostic troubles. Post #10.