Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 07-26-2003, 07:46 PM
Registered User
Join Date: Jul 2003
Location: Sacramento, Ca
Posts: 15
Question A/C vacuum loss

A/C air shifts from center vents to defrost when manifold vacuum is low (WOT). Just started doing it, is there a check valve or reservoir that is common to fail? It just happened and I have not had the chance to look in to it. Thought I would ask this forum for help. Any ideas would be appreciated. Thanks
Reply With Quote
Old 07-27-2003, 02:01 PM
Registered User
Join Date: Aug 2001
Location: Evansville, Indiana
Posts: 8,150
Get a MitiVac hand pump and attach to the supply line in the engine compartment. If the system won't hold vac, you need to fix the leak.

If it does, then you have low vac for another reason, and will have to find out why. Old hard rubber connectors are a typical problem -- they leak, and you have low vac in that line.

1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
Reply With Quote
Old 07-27-2003, 05:23 PM
Join Date: Jan 2003
Location: Florida
Posts: 1,084
Vacum Loss

The locking pump in the 140 shows a connection to the HVAVC, I dont how how it does it or what triggers it, I would check hoses or check valves
Reply With Quote
Old 07-28-2003, 09:41 AM
csnow's Avatar
Registered User
Join Date: May 2002
Location: Mass
Posts: 1,127
I had this exact problem on another car (not MB), and it was caused by a faulty vacuum check valve.
1986 300E 5-Speed 240k mi.
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 03:24 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page