yesterday my ac started acting wierd. the cold air would only come out from the windshield and the sides, but nothing from the center vents nor the foor setting. while driving, i tried all the combination of settings but still only blowing air to the winshield. well today i finally had some time to take a look at the problem and found that a vacuum line was almost about to come loose in the engine compartment right next to the maf sensor. securly plugged it back in and securing the hose with a tie wrap and everything is good to go now, all the vents works again. just wanted to share my story just in case anyone else runs into this same issue.

Thanks Linux, Info like that is always appreciated....I'm glad it was a cheap fix for you.

thank you, this just happen to me when I got something changed last week in my engine compartment. will check, I bet it's the same problem.

Sure enough that's the problem. The center vents are working now, but
I can't figure out what's causing my compressor to not turn on. I'm getting
12 error faults on the reading, hard wire the compressor to make sure it is still working and it gets cold just as long as it's running, but can't firgure out
which of the errors I should check and replace first. I'm going to try and do a search to see if there are articles on problems with the AC compressor turning on.

hope this helped and anytime as you guys have provided so much info for me as well.

Just in time for summer finally fixed the issue with my center vents not blowing any air...THANKS to this thread and others, finally found the culprit why the center vents was not opening. I kept reading about mechanics and DIY guys accidentally unplugging vacuum lines during maintenance. But in my case there was nothing unplugged but simply old worn out rubber vacuum hose that was attached to the white vacuum line. Ran my finger underneath and the rubber just deteriorate. Replaced the old cracked hose and Viola! The center vents opened up like Pandora’s Box what an effing relief . I have been driving two summers with this California Heat unable to enjoy long rides on the AMG. Now just need to recharge the AC and we’re back in business .

Where do you go for recharge in our area?

Good question...haven't figure that one out, going to check Yelp or Yellow pages later

Probably idles a bit better with that vac leak fixed

Nice find
My AC has died and probably needs a recharge. I'll get it looked at very soon as temps are rising and driving the c43 without is not nice with all that engine heat up front and under.....

Thanks .

If your AC was working before and your not getting that ice cold air blowing from the vents,I'm pretty sure it just need a DIY recharge.

I was going to take in for a recharge but endup buying ACpro $35 and I get $10 back if I return the empty can from Wallyworld . Mine was very low took me 15 mins to recharge. Just make sure to follow the easy instructions. My AC is blowing ice cold air now and I'm very happy.

Just had this exact same issue. Replaced condenser and receiver drier, pulled vacuum and recharged system from scratch and my center vents wouldn't give me my fresh cold air!!

everyone please be absolutely certain your system isn't already full before you start shoving more Freon in the system. Cars this age often have clogged receiver driers, worn compressors, or aged condensers that can make a fully charged system stop blowing cold. A lot of times a sensor is old and isn't reading temps right, making it blow warmer air than you want.

the car will absolutely take more pressure than is recommended, but you could very easily over fill it, and the weakest link in the chain is your evaporator. It will pop a leak and you will be completely proper fcked when the shop quotes you $2-3000 to replace it.

Yes, make sure the system is NOT full before adding anymore Freon...if you do that's a trip to the shop to discharge the extra Freon. If you’re not getting cold air there could also be a leak somewhere, the shop will add some type of dye to determine where the leak.

If you feel uncomfortable or don't know how to read instructions and check for symptoms to do a DIY A/C recharge, then take it to the shop and have them check and charge the system. Not all situations are going to be the same but determine which action is best for you.

I’m just glad my A/C is back in service just in time for summer

I cannot DIY fill the AC system in this country for environment protection reasons. That type of work has to be done exclusively in a certified workshop. I'm not going to get it done with the dealer ($$$) but with a Bosch service center. They are good and competent people for all things electric and AC related.

That's not cool! Well at least you'll know the A/C will be fixed right.

It's nice to have the option here to DIY recharge, I've been blasting the AC all week.

Hope you get the A/C going soon!

Booked for Tuesday morning.

hahaha, get it??

No pun intended...I figure someone was gonna get the joke and that would be Sulaco

PIcked her up today and T-Rex now blows ice cold air from all the vents. The tech put some dye in the gaz and oil mixture and I have to get it checked in 2 months time to see if a leak can be found using an UV light detector

I read somewhere that those DIY cans can do more harm than good, is this true? Also, I'm getting a funky smell from the ac right now, have to check evaporator for some build up...