96 E320 AC issues, at my wits end..... - PeachParts Mercedes-Benz Forum

vanzack · #1 07-31-2006, 08:58 AM

I have a 96 E320 that is blowing warm/hot air from the drivers side vents, and blowing ice cold from the passenger side vents.

I have searched and read every post here about it and have already preformed the following tasks:

1. I did the diagnostics on the AC through the onboard computer (by way of the AC display). Everything was fine.

2. I did the error check through the onboard computer and there were no errors (by way of the AC display).

3. Recharged the freon to the maximum capacity. There is no hissing noise behind the vents to indicate low freon. (dont know if freon is the right word - but had this step done professionally so I dont know what to call it).

4. I opened up the Duovalve and cleaned it and put it back together. It looked to be in pristine condition when I opened it but lubed it up anyway.

5. I discovered the flap test outlined at continental imports site and ran through it and I think it failed all over the place.

Just fyi - these are my diagnostic values:

1. 41
2. 40
3. 24
4. 25
5. 25
6. 88
7. 13
8. 52

I see in a lot of places how to test and evaluate the flaps - but nowhere how to fix them. I failed lots of the flap tests, including left and right diverter flaps and left and right blend flaps. Any leads on repairs to flaps?

Still no good results. The problem is intermittent which drives me further insane. When it is hot outside, and when I am driving at 30MPH+ it is the worst. When I am idling it seems to work better, but at its best it is still at least 5 degrees warmer on the drivers vents than passenger vents. At its worst, the drivers blows HOT and the passenger is COLD.

Could the problem be with the vacuum or the vacuum switchover block?

I live in Florida and dont care if I never have heat available to me so if there is a solution that would involve me locking something open to only allow cold air that is fine with me.

ANY SUGGESIONS?

I APPRECIATE ANY HELP OR SUGGESTIONS - I AM GOING CRAZY WITH THIS!!!

mbdoc · #2 07-31-2006, 10:46 AM

That reading for number 7 is the problem!!!!

13 is = to 13bar times 15 = pressure in psi on the high side..

195psi is WAY too low of a high side reading....are you sure of the re-charge??? if not then the expansion valve OR the compressor is most likely at fault..

Is the drier cool OR hot with the system running.?...should be VERY hot.

vanzack · #3 07-31-2006, 12:14 PM

Quote:

Originally Posted by M.B.DOC

That reading for number 7 is the problem!!!!

13 is = to 13bar times 15 = pressure in psi on the high side..

195psi is WAY too low of a high side reading....are you sure of the re-charge??? if not then the expansion valve OR the compressor is most likely at fault..

Is the drier cool OR hot with the system running.?...should be VERY hot.

Thanks for the response.

I had the recharge done at a shop and they used dyed recharge. Could it be a leak somewhere? They said the compressor is still good.

I dont know what a "drier" is - can you explain so that I can tell if it is hot or cool?

Are you also ruling out the possibility of the flaps not working right?

Thanks again for the help.

vanzack · #4 07-31-2006, 10:20 PM

Any ideas out there?

I am about to take it to the dreaded dealer to be overcharged for them twisting a bolt 2 revolutions.

Please help!!

Gilly · #5 07-31-2006, 10:37 PM

"Drier" is the receiver-drier. Under the hood, follow the small hose that come out of the condenser, it will go to a small (a little smaller than a coffee can) tank with a window on the top (round peephole type window, where you look to see if you are low on freon), THAT's the receiver drier.
Gilly

vanzack · #6 07-31-2006, 10:47 PM

Thank you very much Gilly - I will check it out.

brewtoo · #7 07-31-2006, 11:05 PM

Quote:

Originally Posted by Gilly

"Drier" is the receiver-drier. Under the hood, follow the small hose that come out of the condenser, it will go to a small (a little smaller than a coffee can) tank with a window on the top (round peephole type window, where you look to see if you are low on freon), THAT's the receiver drier.
Gilly

And while you're feeling the drier to see if it is hot, peer into that little window on the top and see if you see a lot of bubbles flowing by. If so, your refrigerant level is probably low.