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Discussion Starter · #1 ·
For quite some time my truck has been blowing cold air and occasionally it would get a little warm then revert back to cold. Very inconsistantly consistant!!

So I figured that I was low on freon. So I drained the existing freon to emptuy in so I can put fresh freon back in the truck. When I drained it, I had no moisture of any kind come out. It was only air. Not sure if that was normal or not.

So I started the truck, put the air on low, and put the gauge/freon on the low side of the line. started filling. The compressor would kick on, the PSI level would drop, and after 2-3 seconds, the compressor would kick off. It did this over and over. When the compressor kicked off, the PSI level would sky rocket into the RED. When the compressor was on, the PSI would be in the green.

So I dont have much time to get an accurate reading of the PSI. I haven't even used half the can of freon. So it feels like I'm not getting anywhere. So I took the level that it was showing and put the cap back on. I turned the air on faster and it is blowing nothing but HOT AIR. there is not one bit of cold anywhere in these vents. no matter if i turn the air on 1/2/3 or 4. Its HOT!!

Am I not doing something right when filling it with freon?

With summer upon us, I NEED this cold air to be working. Can anyone help?
 

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"So I drained the existing freon to emptuy" (empty?) I hope you really didn't do that. If you really opened a valve/fitting in the system to release ANY freon, then you also lost your vacuum. Just trying to add freon to a system will not work. You are going to have to "pull a vacuum" on your system now to get freon back in the system.
 

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Discussion Starter · #3 · (Edited)
Thank You for the response. allow me to answer......

When I bought the can of freon from the auto part store. the guy told me to drain the existing stuff out. I didn't know any better. I was assuming since he told me where it was and how to do it, that it was the correct way.

Allow me to begin. I think I'm going to post a picture of what the guy told me to uncap and drain. I'm wondering if I drained the right thing now.

anyways, when i drained "whatever" it was, it was only air. no liquid of any type came out. I couldnt feel anything except "wind". I was expecting to see some type of liquid or colored air but had no such luck.

I do not have a gauge to measure the high side. I only have the gauge on the can of freon that hooks to the low side. if that is indeed what i hooked to.

http://s804.photobucket.com/albums/yy32 ... %20Photos/

the photos you will see have some text written on them. The location that says LOW SIDE, was the spot that the auto parts store guy said to remove the cap and drain. was this the right spot?

what do I do now?
 

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Your compressor does not stay running longer because you are very low on freon. There should be a tag that tells you how much the system will hold, probably at least 3 cans. The system is pulled to vacuum not to get the freon into the system but to remove moisture from the system. Moisture in the system will freeze and interfere with operation. You have a low pressure switch to cut off the compressor in the event the freon level gets too low. The rapid cycling happens because the pressure is low enough that the compressor rapidly pulls the suction pressure down enough to cut off the compressor.

The system is pulled to vacuum so the boiling point of any moisture present drops low enough that it actually boils off and is removed. The system is then held at a vacuum for a period to be sure that the moisture is removed and the system does not leak. Then freon is introduced, the vacuum does aid in getting the first small amount in, but after that the compressor pulls the freon in through suction.

Air conditioning shops remove and install the freon with recovery machines. The freon is drawn out, filtered and stored. The machine is then used to pull a vacuum to remove moisture and assure integrity of the system, then it very accurately measures the freon as it pushes it back in. Without this machine the process relies on your AC compressor to pull the freon back in. The freon is drawn in, compressed and cooled to revert it back to liquid. As the level of freon in your system builds, both the suction and discharge pressure of the compressor increases. When the suction pressure reaches about 30 psi the compressor will run most of the time at idle and the system will blow cold air. When engine speed increases it may cycle on and off occasionally.

You should never drain the freon from the system by releasing it into the air! It is not necessary, it allows moisture to be introduced, and not to mention intentionally releasing freon is against the law. Suction and discharge pressure of your compressor indicates level of charge.
 

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Discussion Starter · #5 ·
did you look at the photos in that link? was what i drained in fact the freon nipple?

what is the most that can happen right now if i leave everything as is? Is the only result, no A/C? Can i damage the truck in any way?
 

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Discussion Starter · #7 ·
odd. I wonder why.

ok anyways........................

OK, I ran in to an old friend today that just happened to have his own used car lot where he also has his own car garage. So I was explaining all my issues to him.

He pulled up a wiring diagram which laid out the battery all the way back to the cluster in the dashboard. After looking at the engine and taking voltage measurements he was able to trace it back to the CLUSTER being the issue. So I at least figured out what the real problem was. I realize I spent wasted $135 but I was intending on having to spend a lot more money to have the truck diagnosed this week at the dealership. So at least we narrowed that down. Nothing to be highly concerned about at the moment. So all is well.

Next thing. I explained the whole A/C issue. He started my truck up, and threw his freon/gauge on and started to fill the system from the same location I was. So the auto parts guy didn't lie about that part. So even though I released all this air out of the system (which could have been freon, and I didn't know it) he at first thought he was going to have to revac the system. he started filling the freon and the compressor was staying on longer and longer...............eventually my truck's A/C was running and blowing COLD air. I'm not sure what he did differently than I, but his freon worked. All is back to normal.

I drove the truck home with the air on and all seemed well.

So it sounded like I may have dodged a bullet.....for now.......

Light is now off for whatever reason and the air is once again cold.

What lesson have I learned? Start off by getting car looked at by a mechanic and not assume I can be a rent-a-cop. Can cost me more in the long run!!!!
 

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you know, firstly, glad you had your battery light ghost fixed.
secondly, all he might have done different was to REALLY apply fitment to the low line coupling. those are tricky, and if not pressed on hard and held in place, fitment does not pop the valve open and nothing goes in.

btw, next time you want to post a photo, post "image code" copy/paste here. will post entire picture ringht into your post. i could not make that link work either, you have part of it missing.

just like this:

 
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