Yup. Take it off and blow through it in normal flow direction. It should flop wide open, then close completely when you quit. Mine barely leaked past. Battery voltage applied should lock it closed.
However, low flow at idle can still be a bad aux pump -- verify that you get power when the key is switched on (and check the temp sensor fan beside the glove box, too -- it's on the same feed). No power, the pushbutton unit won't turn it on as it supplies the ground. You can verify that it's working by the vibration of the rotation by setting the temp wheel to the hot click and push the defrost button -- so long as the engine temp is above 40C, the pump should be on. You can check the Pushbutton unit by unplugging the pump and checking that there is battery voltage across the power pins to the pump under the same conditions. Mine works much better now, still rather cool at idle, but no great rush of heat and I don't freeze sitting at stop lights. Not sure about the aux pump, I'll be checking that out next week as I'm taking a week's vacation to start the spring stuff and the weather should be decent. I also had a bad connection to the engine temp sensor that I re-soldered, but have not verified yet. Peter _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
