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Old 01-12-2008, 07:42 AM
llando88 llando88 is offline
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Location: On The Move
Join Date: Jul 2003
Posts: 14,818
Mein Auto: Ram 2500 4x4
Thought I would post the current results of my attempt at DIY today.

I kept researching this and found a fairly simple procedure to recharge the refrigerant.

I went to the local Autozone and bought a recharge kit ($16.99) and a can of R-134A refrigerant.

Following the instructions on the kit, I was able to re-charge my system so things are much much cooler inside, and the 'hiss' sound is completely gone.

Additional information is at this company web site, in particular the video they had here:

I also found this thread helpful:

I asked Master Wingspan (age 11.) to snap some pictures, they appear below. (bear in mind we are not professionals.)

Some notes:

- The low pressure recharge port is on the firewall, see me pointing to it in picture one. In this picture I've removed the cap from the recharge port.

- After attaching the kit, it read about 20 psi. This was on the low end. I filled until the pressure read about 29 psi. This consumed the one can I had bought. The next picture shows the kit, with the can attached, on the recharge port.

- The last picture shows the can, plus the fittings on the recharge kit. The car end of the kit is a snap-ring fitment. It will only fit on the Low side. One tip - have your right thumb on the top of the attachment fitting as you pull up on the ring with your left hand, you have to overcome the residual pressure on the line, push down, then release the snap ring.

- Wear safety goggles and gloves.

The process is fairly straightforward.

1) turn the gauge handle upwards, lifting the piercing pin all the way up
2) shake can
3) screw the can onto the gauge handle
4) start engine and set to max cool
5) attach the quick disconnect fitting
6) turn the gauge handle clock wise to pierce the can
7) turn the gauge handle counter clockwise until the refrigerant starts to flow.

Trust me, you will hear this. I waited about 5 minutes before I realized that nothing was coming out. Doh. I had not unscrewed the gauge handle enough.

8) while charging, rattle the can and move it between 12 and 6 o clock
9) continue until can is empty (about 15 mins in my case).

You can check the pressure on the low side while doing this process by screwing the gauge handle all the way in.

I used one can and my lp pressure went from 20 to 29 or so. Not too scientific. I think the whole system is 2.2 lbs of refrigerant, but don't quote me on that.

Car info: Car is a 2003 330i bought from new. I now have about 47.7K miles.

Hope this helps. I did not find a lot of recent DIYs on this, so thought I would post the info.

Oh, I'm going to cancel the appointment at the dealer on Monday.


I am not a professional mechanic, don't do anything stupid on account of what you read on the internet, you proceed at your own risk, look before crossing etc. etc.
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“Character is doing the right thing when nobody’s looking. There are too many people who think that the only thing that’s right is to get by, and the only thing that’s wrong is to get caught.”

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Last edited by llando88; 01-12-2008 at 07:49 AM.
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