W211 Air Con Problem

[jazzenator]

Hi
I have a 2004 E320 CDI.
I have just had my air con regassed and serviced at a MB dealer. The reason was that I was having problems in start stop traffic or in the city the aircon wouldn't cool the air (even if I turned the temp all the way down) however, if I were to accelerate hard, cold air would be blown into the cabin.
Today on a long journey, I once again noticed similar problems as before, furthermore, about 4 hours into the journey the air con once again stopped cooling the air, infact the air was warmer with the aircon on then swithched off. Anyways, I switched it off for about 15 mins or so and upon swithcing it back on there wasn't a problem.
Can anyone explain the reason behind this.

Thanks

 

[horgantrevor]

when you start the air con do you feel the system engaging as a sudden draw from the engine and after a while dose this go to say the air con dose not work

it may be a loose connection or earth wire

have a look some times it the small thing that cause the most prob


i had a friend who's car would not start a mechanic had changed the allternator , coil pack and many more parts with no luck , i told my friend it cant be that big a prob as the car was fine . well after he had spent a lot of monet and wasted a few weeks he asked me to look and with in ten min car was running at no cost . a small thing happpened the chip for the key was on the mat drivers side it had falling out of the key
.

ie ; i hope its some thing small have a look at the wiring the switch for turning on and off may be faulty
good luck i hope this helps

 

[jazzenator]

hi
thanks for the reply. To be honest I have not noticed that. It just works better when the engine is at high speeds and feels that it is not doing much when the car is idling.
Also it stopped during the long journey and a 15min rest seemed to 'revive' it. Even if it were a loose wire where do I look for it?
Any other thoughts.
Thanks.

 

[Donk]

Bit of a long shot but...

Dont suppose you have the luxury climate control do you? Reason I ask is that I had problems the other day trying to keep the front cool and set to auto the fan was always blowing hard and the car interior temp just did not feel right according to what I had it set to. I then noticed the centre glove box was being pumped full of hot air (made my sweets all sticky bah) and the centre console was warm to touch. Turns out that whoever was in the back seats last had turned up the air con to full, so no wonder it was hard to chill the cabin properly as the system must have been fighting against itself front to rear doh. Once turned down all seemed back to normal.

I dont know if its supposed to work like that, or maybe mines faulty as well but thought I'd point it out just in case

 

[MB TECH WARRINGTON]

faulty duo valve can cause this fault, replaced many of these, sits below brake master cylinder, bit of pig to change,,,,

 

[jazzenator]

Bit of a long shot but...

Dont suppose you have the luxury climate control do you? Reason I ask is that I had problems the other day trying to keep the front cool and set to auto the fan was always blowing hard and the car interior temp just did not feel right according to what I had it set to. I then noticed the centre glove box was being pumped full of hot air (made my sweets all sticky bah) and the centre console was warm to touch. Turns out that whoever was in the back seats last had turned up the air con to full, so no wonder it was hard to chill the cabin properly as the system must have been fighting against itself front to rear doh. Once turned down all seemed back to normal.

I dont know if its supposed to work like that, or maybe mines faulty as well but thought I'd point it out just in case

I dont think it is a luxury climate control. People from the back can only operate the airvents and not the temp. The temp in mine is adjustable by dials.
My car is still under warranty should they replace the duo valve?
thanks

 

[toxic]

Hi if under warranty take it back and get them to fix it, don't be put off, and explain that if this problem continues after the warrant has ran out you would expect them to keep trying to fix it free of charge, if needed get them to try everything and change everything, especially the costly bits, ask them to supply a loan car and not to return it till it's fixed ..note down your millage before you drop it off

regards Mark.

 

[MB TECH WARRINGTON]

faulty duo valve can cause this fault, replaced many of these, sits below brake master cylinder, bit of pig to change,,,,

have you had the duo valve checked as i mentioned above, these can fail and eventually can cause either blowing always hot or cold depending which way it fails,