Have a question about my ac system mainly the low and high port ?

I'm not sure if that's what there called. But when I open the one closest to the air filter housing. It's sounds like air escaping. Honestly I'm not sure if it's that one. I will have to double check which one it is. But it does it every time you open the Cap is it normal. I think I remember opening it about a year ago and it did the same thing. Air is still blowing cold so it can't be anything major right ? Is that what there called the ac low and high port ?

They should not leak when you remvoe plactic cap... if they make noise then they are leaking and you have bad schrader valve and need system repaired.

Low one is on Accumulator and is the larger of the two as they are different sizes to prevent peeps from messing up

They should evac and save refridge
Replace valves
Then vacuum down and recharge,

Wow that sounds expensive. This isn't something I could do is it ? I mean I'm a pretty good handy man. I mean is it bad ? to leave it how it is. If my air is still cold ? Should I not even mess with it ?

A little leakage is OK but if you pop the cap off and hear it leaking then yea its an issue...

The Valve stem is leaking and needs to be replaced and around here to vacuum the system down and then refill it is like $150. You do NOT want to try to repair it yourself. The "Freon" that comes out will "burn" you as you try to replace the small little insert and you will rapidly loose all of your Freon to the atmosphere. Venting something like that technically is against Federal Law... Although letting it leak out isn't... 

If you don't vacuum the system out you will get air and moisture into your system which will cause you much more grief.

Rodney

But I have been driving around like this more than likely for a long time now. How come nothing has raised up. Problem wise. So I can't do this myself. Like maybe autozone or some other places Carey's the speciality tools I can rent or etc.

When you remove your old valve stem you will be evacuating the system. If there is enough coolant still left in the system you will get frostbite.

You will need the system vacuumed and refilled. I am looking into this myself for my system and I think I will be buying a vacuum pump, the gauge manifold and some parts to change out some seals on mine and then try to get it back up and going.

The cap SHOULD prevent it from leaking if you keep it on and it seals tight...

So in that case don't remove the cap...

Rodney

If you have a set of gages ($59.00 at Harbor Freight) you can easily purge the system with no fear of getting frostbite. You connect the high and low couplings to the high and low ports of the A/C plumbing and you open up the shut off valves just under the gage. While the system is draining you will see frost build on the lines and it will be extremely cold so do not touch. After this is done you can then replace the Schrader valve. If you have an old Freon can connector in your possession (obviously you do since you refill yourself) all you have to do is connect the quick connect coupling to the A/C port (with the shut off valve close of course) and then slowly back off the valve to let the Freon escape. This will allow you to evacuate the system with no fear of frostbite. However, you want to avoid breathing the gases. The Freon has oil mixed in and the oil vaporizes when you open the system to atmosphere. This gas/oil vapor is carcinogenic. Where a mask while opening the valve and then walk away. After everything leaks down you can then replace the valve.

However, there is one major problem. Before you can refill the system with R134a you haven to pull a vacuum on the system to remove any moisture that may have gotten in while you had the valve removed. A cheap vacuum pump capable of puling a good enough vacuum for an A/C system will cost you no less than $100.00. Most are $150.00+. Then you have about $50.00+ of R134A you have to buy to refill the system! You will easily exceed $200.00 to do this the first time. You will most likely exceed $250.00 and it's possible to exceed $300.00. You can do it for under $200.00 if you order everything ahead of time from discount suppliers (from china) and wait 30+ days for everything to arrive.

There is one more option and I have not even tried this yet. For $100.00 there is a tool on AMAZON.COM that claims to allow you to change a Schrader valve with NO FREON LOSS!! http://www.amazon.com/Loss-R134a-Valve-Remover-Installer/dp/B011T6LUI4/ref=sr_1_29?s=automotive&ie=UTF8&qid=1437171136&sr=1-29&keywords=R-134a+Service+Port+Adapter

I've already hinted to the wife that I NEED this tool! Merry Christmas! It comes with adapters for the low and high pressure ports. I have no clue how it works. It sounds pretty sketchy, but if it works it will change life forever for the DIY types! I had a leaking valve on my Dakota R/T for 4 years and I just kept throwing money away on more Freon. I finally broke down and bought enough Freon to do the job and changed the whole valve out. I was out nearly $100.00 for the new valve and all new Freon. Had I known about this little device I would already have purchased it.

Of course, you could just take it to a shop with the APROPRIATE HVAC equipment. They will have a Freon recovery system that will capture all of your existing Freon and then put it back in when they are finished servicing the system. The typical cost for such a service is under $200.00. So if this is a 1 time deal you would save money by paying a professional to do this. If you have 4 cars like I do and you do all your own work then it may be a good investment to buy a set of gages and a vacuum pump.

Also, R134a is supposed to be environmentally friendly (does not deplete ozone). That is why you can buy it without a license. In other words, the EPA, CIA, and the FBI won't be showing up at your door if you leak this stuff to atmosphere. If you had an older car with R12 it would be totally different! I think all cars made after 1994 have ozone friendly R134a Freon.

A couple things.. The low pressure port is rebuild-able and that tool will work fine for it. High pressure port has to be removed as a unit. When you buy a rebuild kit it will have 3 shraeder valve inserts, an o ring and a new high pressure port.

I used one of the shraeder valve inserts and the spare oring on the low side switch. You need a valve tool to change out the insert. The Oring seals the low pressure switch to the access port. The low pressure switch can be swapped out without issue as long as the shraeder valve is working well.

I used another of the shraeder inserts on the low pressure port.

The high pressure port is one piece and is not rebuiildable. It uses an 8 sided pattern so you need to use a crescent wrench to install it. I used a pair of vice grips on mine.

I have one of the harbor freight gauge kits. It seems to work nice.

I didn't want to pay a bunch of money for a vacuum pump when I have an air compressor so I bought the venturi style vacuum pump from harbor freight. I would get the vacuum pump. I could only go to -20 and you really want to go to -30.

In MY system I had no pressure so I had to vacuum out the system to get rid of the moisture. I also used a special formulation of 134a that had oil and some additives that are supposed to clear out any moisture.

One note about releasing the 134a... To vent your system like mentioned is technically against federal law and if caught it can cost you jail time and a bunch in fines so do yourself a favor and have it vacuumed out and recovered. You can work on and charge the system once it has been emptied. 

So don't just release the 134a if you can help it. By law you are allowed to let a little vent while hooking up gauges etc but to vent the system on purpose is a big no no... Its like taking the convertor off your vehicle...