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Discussion Starter #21 (Edited)
Thanks for the test results. I am just wondering if you have enough refrigerant in the system. You may have very little in liquid form. I would add a can (12 ounce) of refrigerant (you can get from WM for $4, if you have the piercing adapter) and see what happens to the readings. Make sure you PURGE the air from the manifold hoses by releasing some refrigerant from the charging side prior to charge.
I hope that's all it is, it's a freaking inferno driving a black E320 that's been sitting in the 100 degree sun all day...

Yeah, I did notice air trapped in the hose between the manifold and couplers when putting it away.

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Use straight refrigerant only or with dye. Do not use the ones with sealer or added oil.
 

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Read the instructions!

Do NOT open the red valve with car running! This is very high pressure and your can of refrigerant can EXPLODE!

Purge air in hose by loosening fitting at the gauge.
 
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Discussion Starter #24
Read the instructions!

Do NOT open the red valve with car running! This is very high pressure and your can of refrigerant can EXPLODE!

Purge air in hose by loosening fitting at the gauge.
I definitely will, I don't do anything without researching first. lol I was a little too eager with my last comment because I'm tired of this California heat without an AC.. Thank you though!

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Ideally...........system should be charged by refrigerant weight. When you use gauges, you must compensate for ambient temperature. Do NOT use outside temperature sensor on car.


Temp-pressure-chart-33776F1.jpg
 
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Discussion Starter #26
Ideally...........system should be charged by refrigerant weight. When you use gauges, you must compensate for ambient temperature. Do NOT use outside temperature sensor on car.


View attachment 2656302
Man, I'm sure $4 piercing type cans of refrigerant no longer exist here in California, because I couldn't find any anywhere. Had to pay $20 just for one, $10 of which get refunded when I return the can, and now I need to wait for a self sealing type tap for my manifold gauge... Although the guy at AutoZone wanted to sell me the same A/C Pro gauge I already had lying around for almost $30. Can I use that with the can, or is it junk?


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As long as it's straight 134 and not one of those with oil, sealant, crap.
 
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Discussion Starter #28
As long as it's straight 134 and not one of those with oil, sealant, crap.
The can I bought doesn't list any additives at all, but earlier this year I did use this A/C PRO one which is where I got the gauge from. Are the additives that bad, hope I didn't screw up...


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Depends. In an ideal world, you would do an evac and recharge the freon by weight. That way you get rid of all possible contamination.

Depending on how many cars you have, it might be worth buying a vacuum and a AC scale and doing it yourself. If it's just that one, then eeeeeeh. Yolo?
 

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Man, I'm sure $4 piercing type cans of refrigerant no longer exist here in California, because I couldn't find any anywhere. Had to pay $20 just for one, $10 of which get refunded when I return the can, and now I need to wait for a self sealing type tap for my manifold gauge... Although the guy Aut


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Man, I'm sure $4 piercing type cans of refrigerant no longer exist here in California, because I couldn't find any anywhere. Had to pay $20 just for one, $10 of which get refunded when I return the can, and now I need to wait for a self sealing type tap for my manifold gauge...
And...........I believe you have to return the can within 90 days to get your deposit refunded.

Piercing type cans are no longer legal to sell in California. I bought a case from an out of state vendor on Ebay, No deposit required.
 

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Discussion Starter #31
Ideally...........system should be charged by refrigerant weight. When you use gauges, you must compensate for ambient temperature. Do NOT use outside temperature sensor on car.


View attachment 2656302
Okay, so it's 90F outside this afternoon, and I did everything properly, purged at the manifold fitting like you said etc. I used up the 12oz can and got it to the level pictured below, not quite to the level for 90F on your chart, but I noticed that the air in the cabin was definitely starting to cool down a bit.

Usually, when the AC did work, I would have to take the car up to speed to get frigid air from the AC, so I'm going to take it to AutoZone to return the used can and buy a new one and see how the AC feels. You guys let me know if it should be fully cooling by now, or if I do need a bit more from another can! Thanks!!


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Discussion Starter #32
Okay, its definitely frigid now, not Mercedes cold, but enough to get mom to complain lol

Don't now how people in the videos get 44F air from their car just sitting in the driveway. I have to drive a litte to get it cold.

Is it normal for the cap on low pressure port to become extremely tight after I just finger tighten it before? The high pressure one was no were near as tight. I had to use pliers to loosen it every time.

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The best way of course to evacuate the system and charge 3 * 12- ounce cans (35 ounce is the spec). Since you are not doing this and just adding refrigerant, I would slowly add refrigerant and check sensors 3 and 4 (the heater temp sensors) when the temp setting is LO LO. The two sensors should within 2 degrees F and sensor 5 close to 35-40 degrees F. When two heater sensors are close to each other it indicates that the liquid refrigerant is reaching to the driver's side to expand and cool the driver's side airflow. The passenger side and drivers side airflow temp from the center vents should be about the same (that you can check it with a thermometer if you have one).
 

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Caps on the ports shouldn't tighten up by themselves to the point where pliers are required to remove them again. Check the valves with soapy water to see if they are leaking. Some people tap the valve stems with a pen to reseat the valves after removing the quick connects.

As a side note: final pressure should be read at 1,500 to 2,000 engine RPM.
 

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You need to obtain and post the sensor values and fault codes (if any). The sensor values should be obtained with and without the engine running, a/c turned on.

If you have a single electric fan unit (between the radiator and the engine), the fan may turn on with the engine running, and turn faster if the high side refrigerant pressure is higher than 14 bars (200 to 210 psi). If the compressor is not running the fan will not run due to a/c. The code you have indicates that the pressure information is not communicated to the instrument cluster. If could be temporary, you could clear it and see if it comes back.

Finally got the codes from the Climate Control System. They are:

Code # - Engine Off / Engine On
01- 80/84
02- 76/76
03- 78/80
04- 80/82
05- 80/80
06- 73/82
07- 00/00
08- 73/73
09- 27/27
10- 4.3/3.8
11- 0.3/0.3
12- 4.2/4.2
20- 3.2/3.2
21- 32/46
22- 00/00
23- 32/32
24- 11.5/13.3
40- 164/164
41- 85/85
42- 104/104
43- 136/136

So the one that caught my eye was Code 07 "refrig pressure." It would appear that the system is out of refrigerant. The car has been in storage for about 2 years, so I assume this is normal?

Do you see any other values that look off?
 

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1998 E320 base sedan @ 160kmiles
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Right, you have no refrigerant left. You could try charging it with a can of refrigerant and see what happens. I would not fully charge the system, as you definitely have a leak somewhere, possibly dried up o-rings / gaskets over two years of non-use. It will likely leak again, to what degree, I do not know. It would be an idea to put the refrigerant with dye in it so you will know where it will leak again. So far everything else seems to be fine. After you put the refrigerant, take another set of readings.
 

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Anywhere the lines are connected to components like the compressor, drier, condenser, expansion valve etc., as well at low pressure / high pressure valves connections, line-to-line connections. Compressore have a working life like any other mechanical component. Original compressors had a design flaw which caused them to seize, especially when the lubrication is lost along with the refrigerant over time. Replacement of the original compressor is highly recommended when the system is opened up to fix the leaks. A seized compressor replacement will require replacement of many other components, and flushing the lines which is expensive and labor intensive. So it is preventive maintenance to replace an unseized old and tired compressor.
 

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All very good points. I'm going to start with filling the system w/ refrigerant and go from there.
Is there a chart of fluid capacities? I'm trying to figure out how much R134 this system takes.
 

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Depends on the car, but usually there's a sticker somewhere in the engine bay that lists the capacity of the refrigerant. On the W210, the sticker is on the ECU coffin box lid. 2.2lb to charge.

If yours is truly empty, you need to draw a vacuum first. Simply dumping freon won't work, and in fact might perform worse.
 
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