Here are your problems. You have vacuum leaks somewhere. Could be the center vent element or could be be other places in the system. Sounds like it sometimes pulls enough vacuum to open the vent. As far as compressor goes that is the classic clutch issue. The sensor in the compressor senses it slipping and shuts it off. You can get shims I believe to tighten it up but otherwise replace compressor clutch.
Sent from my iPhone > On Mar 8, 2016, at 4:12 PM, Dan Penoff via Mercedes <mercedes@okiebenz.com> > wrote: > > As I get the 350SDL sorted out, I'm starting to turn towards the ACC system. > It works, sort of, but has some quirks that I know are not right. > > I'll be doing some research in the next couple of days to learn what I can > but I figured I would toss things out here in the hope that maybe someone > might recognize some of these and have some input. So here's what's going on: > > The good: > > Fan speeds seem to be good and somewhat temperature dependent. If the temp is > set low and it's hot, you get high fan speed until things cool down, which is > what it should be doing. Same in reverse with heat. > > The various modes sort of work correctly for the most part (more on this > later.). Heat comes out the floor, defrost out the top of the dash. > > AC is charged and has proper pressures. Definitely gets cold. > > The not so good: > > Center vents are weird. They do work, but rarely. They only seem to come on > during transitions when the system is close to the desired temperature. For > example, when you want full cold, you get defroster vents, not center vents. > When the system has almost reached the desired temperature, the center vents > kick in. I think this is important to note since I realize that the system > default is defrost - the center vents do work, just not for a lot of the time. > > The aspirator fan wasn't working and the thermistor in the ceiling grille was > filthy. It has been cleaned and I have the aspirator fan working. > > When the AC is run, it comes on and makes plenty of cold. But - once the > compressor cycles off the first time, it doesn't come back on until the car > is shut off. So you get cold until it cools down, then you get ambient air - > the compressor never comes back on. > > The PO threw an evaporator temperature switch at the car, which they claim > fixed the problem. It doesn't appear that's the case. > > So, to summarize: > > Center vents are wonky > AC compressor won't cycle back on > > I'm all ears, folks. I know the Gen 1 ACC system, but the later system is a > bit more complex and not something I'm familiar with. > > Thanks, > > Dan > > Sent from my iPad > _______________________________________ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
