A/C Recharging
Thread Starter
Super Member
Joined: Jan 2008
Posts: 586
Likes: 2
From: Springfield, Missouri
03' E55 Techtite Grey
A/C Recharging
I was wondering if anyone knows how to recharge the A/C system in our cars and if we can do it ourselves or do we have to take it to the dealership? Are there any videos or tutorials out there that instructs you on how to do it?
Thanks!
Thanks!
MBWorld Fanatic!
Joined: Jan 2004
Posts: 7,092
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
I am in the middle of a compressor install in the garage. You can add some R134 to the system on the low side. The large pipe on the driver side just in front of the fuse box with black cap on it. NOT NOT the black cap on the left side (they are right next to each other) connected to the smaller hose. That is the high pressure and will roast your system if you add it in there. My apologies this is all 2nd grade to ya. Just covering my **** in case you added 2 cans to the high side and blew the thing apart. 
Perhaps add a tiny bit of freon and then see if that improves the system somewhat. If not STOP and go to dealer.
They have a machine that adds the factory amount of freon you need and removes any extra that could be slowing down the system.
You overcharge it and you are looking at major problems with these $$$$ systems.
Worst part about our systems is that the compressor CONSTANTLY runs on these cars. It's spins up and down like a turbo depending on need. No old time clutch system..... so it's hard to put gauges on the thing and judge freon from them like in the old days.
You could have well under the recommended amount and gauges show you are 100% fine while the compressor is spinning like a jet engine to keep up.
Add a tiny bit and then run it to stealer and have them top it off. Better safe than sorry with these cars.
Perhaps add a tiny bit of freon and then see if that improves the system somewhat. If not STOP and go to dealer.
They have a machine that adds the factory amount of freon you need and removes any extra that could be slowing down the system.
You overcharge it and you are looking at major problems with these $$$$ systems.
Worst part about our systems is that the compressor CONSTANTLY runs on these cars. It's spins up and down like a turbo depending on need. No old time clutch system..... so it's hard to put gauges on the thing and judge freon from them like in the old days.
You could have well under the recommended amount and gauges show you are 100% fine while the compressor is spinning like a jet engine to keep up.
Add a tiny bit and then run it to stealer and have them top it off. Better safe than sorry with these cars.
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Joined: Dec 2008
Posts: 4,411
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From: Socal, Chino
E55 2006 / CLS55 / S450 / Jag XKR2011
I am in the middle of a compressor install in the garage. You can add some R134 to the system on the low side. The large pipe on the driver side just in front of the fuse box with black cap on it. NOT NOT the black cap on the left side (they are right next to each other) connected to the smaller hose. That is the high pressure and will roast your system if you add it in there. My apologies this is all 2nd grade to ya. Just covering my **** in case you added 2 cans to the high side and blew the thing apart.
Perhaps add a tiny bit of freon and then see if that improves the system somewhat. If not STOP and go to dealer.
They have a machine that adds the factory amount of freon you need and removes any extra that could be slowing down the system.
You overcharge it and you are looking at major problems with these $$$$ systems.
Worst part about our systems is that the compressor CONSTANTLY runs on these cars. It's spins up and down like a turbo depending on need. No old time clutch system..... so it's hard to put gauges on the thing and judge freon from them like in the old days.
You could have well under the recommended amount and gauges show you are 100% fine while the compressor is spinning like a jet engine to keep up.
Add a tiny bit and then run it to stealer and have them top it off. Better safe than sorry with these cars.
Perhaps add a tiny bit of freon and then see if that improves the system somewhat. If not STOP and go to dealer.
They have a machine that adds the factory amount of freon you need and removes any extra that could be slowing down the system.
You overcharge it and you are looking at major problems with these $$$$ systems.
Worst part about our systems is that the compressor CONSTANTLY runs on these cars. It's spins up and down like a turbo depending on need. No old time clutch system..... so it's hard to put gauges on the thing and judge freon from them like in the old days.
You could have well under the recommended amount and gauges show you are 100% fine while the compressor is spinning like a jet engine to keep up.
Add a tiny bit and then run it to stealer and have them top it off. Better safe than sorry with these cars.
Good advise, I just did AC service which add freon I guess.... I paid $120 and now its really cold. I just want to play safe with these cars...
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From: Cypress, TX
'06 E55, '15 Jeep SRT8, '94 Mustang GT
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From: Jacksonville, Florida
2006 E55 AMG --old cars -- E39 M5, 2.7tt Audi S4, E36 M3 **Ducati 996, 748
Can you take a qyuick picture of the black cap? -- Just to make it really clear. As long as I am sure - I dont mind adding a little R134 to my system.
I am in the middle of a compressor install in the garage. You can add some R134 to the system on the low side. The large pipe on the driver side just in front of the fuse box with black cap on it. NOT NOT the black cap on the left side (they are right next to each other) connected to the smaller hose. That is the high pressure and will roast your system if you add it in there. My apologies this is all 2nd grade to ya. Just covering my **** in case you added 2 cans to the high side and blew the thing apart.
.
.
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Thread Starter
Super Member
Joined: Jan 2008
Posts: 586
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From: Springfield, Missouri
03' E55 Techtite Grey
This talk about it being $$$ to fix a mess up and it being difficult to read pressures makes me just want to take it to the dealership. How much will it be to have them fix it? $120? 
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MBWorld Fanatic!
Joined: Jun 2009
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From: Cypress, TX
'06 E55, '15 Jeep SRT8, '94 Mustang GT
Fix what? What exactly is the system doing? Not cooling at all? Intermitent cooling? Almost no airflow?
MBWorld Fanatic!
Joined: Jan 2004
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
Yeah what symptoms are you having?
Common symptoms of low freon are drivers side being warmer than passenger. Having that?
Sorry to spook you on adding freon. Many guys have added part of a can and drove away happy and ice cold.
Just that you could have clogged expansion valve, evaporator, a bad sensor, or a few other things and throwing freon at it would end up damaging the system when you overcharge.
Common symptoms of low freon are drivers side being warmer than passenger. Having that?
Sorry to spook you on adding freon. Many guys have added part of a can and drove away happy and ice cold.
Just that you could have clogged expansion valve, evaporator, a bad sensor, or a few other things and throwing freon at it would end up damaging the system when you overcharge.
Thread Starter
Super Member
Joined: Jan 2008
Posts: 586
Likes: 2
From: Springfield, Missouri
03' E55 Techtite Grey
No the system works fine. It just isn't as cold as it use to be making me think that it may just be getting low. What do you guys think? It gets colder as I'm moving with air going through the radiator. When at a stop it isn't hot by any means but isn't as cold.
Junior Member
Joined: Aug 2009
Posts: 54
Likes: 3
2018 Range Rover V8
Yeah what symptoms are you having?
Common symptoms of low freon are drivers side being warmer than passenger. Having that?
Sorry to spook you on adding freon. Many guys have added part of a can and drove away happy and ice cold.
Just that you could have clogged expansion valve, evaporator, a bad sensor, or a few other things and throwing freon at it would end up damaging the system when you overcharge.
Common symptoms of low freon are drivers side being warmer than passenger. Having that?
Sorry to spook you on adding freon. Many guys have added part of a can and drove away happy and ice cold.
Just that you could have clogged expansion valve, evaporator, a bad sensor, or a few other things and throwing freon at it would end up damaging the system when you overcharge.
MBWorld Fanatic!
Joined: Jun 2009
Posts: 4,429
Likes: 61
From: Cypress, TX
'06 E55, '15 Jeep SRT8, '94 Mustang GT
Go into the hidden climate control menu and post your values for 1-10 after letting the car & system warm up. Give it about a 15 minute drive or so.
MBWorld Fanatic!
Joined: Jan 2004
Posts: 7,092
Likes: 13
From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
I agree. Let's see what it looks like. Gotta admit, I am pretty clueless on AC systems. I can swap out the compressor granted, but diagnosing is pretty tough.
