oofie910

hi guys, newb here, hope someone can help me.

i just bought my e320 as a second car, however, there seems to be a problem with the climate control. it can blow heat and cold air, but whenever i step on the gas from a stop, the air gets diverted from the vents to the vent near the windshield. i duno why it does that, i think it tries to blow air to the windshield whenever i step on the gas. is there anyway to stop this. ive already tried directing the air toward the vents and foot vents, but it still does that. then everything goes back to normal (air blowing thru correct vents) when i
1)stop and 2)when cruising the freeway (not stepping on the gas all the way). i hope someone can help me here. thanks guys. btw, very informative forum u got here.

sosh

Sounds like you have a problem with the vacuum control system for the vents. The engine vacuum that is used to power them always decreases in pressure during acceleration, increases on decelleration but the vents should not move from that change. Dealer is your best bet for repair

oofie910

really? any of u guys have an idea how much it will cost me? thanks for the reply by the way.

sosh

Cost?? Can't say as its not known exactly what parts are needed. However, for this I do suggest a dealer as it will be less expensive in the long run meven though labor rates are higher. Troubleshooting time and install time should be lots less with no guessing

JLLG

I have the exact symptoms in my climate control system (97 E320) but have never taken time to have it looked at. Anyone else?

SL55&E55

go with the dealer on this one.

aTOMic

there are several exposed vacuum lines and (at least on the M104 straight six) several you can get to easily. Mine had one line broken, at a right angle in the tubing near the yellow connector above the EGR valve under the plastic coil cover. The replacement part is molded into the 90 degree curve and is cheap from mercedesshop.com. Get some yellow connectors too and check the vac lines where they curve and where they rub on engine parts.
Sorry to tell ya that I did not have the HVAC problems you do, but it's a place for you to start.
HTH,
-Tom

Steve 90TTZ

Did you get this fixed Atomic?

I found out that one of my hoses was disconnected, but now I am having the same problem as described above. On acceleration the air is diverted to the windshield, on deceleration and cruising it works normal. Is this normal for all of our W210s?

Is there supposed to be a check valve in the hose that runs from the intake manifold to the vacuum junction box under the hood?

Thanks,
Steve