View Full Version : 2001 1.8tqm- where does the vacuum line from the clutch vent switch go?

4A Play
09-29-2016, 02:31 AM
So I have an issue with over reving between shifts. Did a little research and discovered that the clutch vent switch being have can cause this. I go and check my pedal assembly out. And there is no vaccum line attached to my switch.

In a 2001 1.8t qm, should this switch be hooked to vaccum? Where does this vaccum go? I do not have any loose vac lines floating under the dash. Went to the junkyard and verified in a pre-facelift that the switch is actually hooked to vaccum on v6s at least. Wasn't sure if it should be on mine.

Thanks guys!

09-29-2016, 07:20 AM
In the 2001 1.8T manual car, there are 2 clutch switches. One is for starting the car (engages at the bottom of the clutch throw) and the other is for the ECU to know when the clutch is depressed (located near the top of the clutch pedal when it's at rest).

Both switches are electronic, no vacuum lines. It is possible for these switches to go bad or need adjustment, though. You can check the ECU's clutch switch operation in VAG-COM / VCDS, or possibly with a multimeter.

4A Play
09-29-2016, 06:03 PM
Ok. That's odd because the switch in my 2001 is the type that has a vaccum line nipple on it and the two wire connector going to it. No vaccum line though.

What is the switch adjustment procedure? I can see it threads closer to the pedal to adjust the release point but where is the sweet spot? I played with it a little, adjusted it all the way back so that the pedal is just pressing the switch In when my foot is off the clutch. I figured this would cut fuel sooner into my clutch pedal depression and eliminate my over rev. But that just put my car in limp mode whenever I was reach boost. I pushed the switch more towards the clutch pedal and then it was shifting as usual but over reving again. I grabbed two switches at the junkyard to see if mine is faulty but would rather adjust mine if that's all the issue is.

09-30-2016, 11:56 AM
When there is vacuum controlled cruise control then switches are vacuum and the vacuum line goes thru the wall to the pump under the servofluid reservoir.
My son has an code AJL TSQ.

09-30-2016, 12:40 PM
All DBW cars retained the clutch switch that was fitted to DBC (1995 - 1999.5) models. These DBC models relied on vacuum to disengage cruise control. The DBW cars have cruise built into the engine ECU, so the vacuum nipple will be vacant.

4A Play
09-30-2016, 04:04 PM
Awesome! Thank you guys! So is there an actual switch adjustment procedure? Or the switch is either engaging or not engaging? Does the switch need to be released at a certain point in the clutch pedals throw or anywhere in the pedals arch?

Hope that makes sense.