Brake Booster Check Valve
Hello Fellow DN'ers,
I inherited this basket case that a previous shop has done some tinkering. There has been some modification of the vacuum line and sensor between the engine and the booster. The electric vacuum pump was completely dead, so I replaced it with OE. That is now working and I have a pedal when ICE is off. Code sets when car is in turbo boost. As stated, someone cut up the plastic vacuum line and installed a sensor between the engine and the booster. There is a check valve between the electric pump and the booster, but NO check valve between the engine and the booster. Seems to me there should be. Trying to get some theory or at least an illustration of what this line should look like before the hacking.
Current configuration is a line with a booster tee'd in the middle. One side goes to the electric and one goes to the engine. Sensor cut into the section from engine to booster. Any help or theory of what I'm missing would be appreciated.
Service information makes it sound like there is no tee. The hose goes from the vacuum pump to the booster. The sensor is mounted on the hose AT the booster.
Yes, many pictures show it there. My vehicle has a T at the booster. No sensor there. No modifications at the booster; looks all original there.
So the second image from my previous post is not right. How about this one? I know its not a tee at the booster but the sensor isn't located right against the booster on this one
Better, but the vacuum pump is different than mine. Possible that the booster connection is simply no visible in the picture.
Looks like the sensor is mounted at the booster and the check valve (A) is the tee. Looks like the engine and the pump connect there based on the one diagram. The grey hoses look to be them but I cant be sure. That 3rd image with the check valve doesn't show the sensor on the booster so not sure if its your application. Images courtesy of ProDemand
I have that vacuum pump. I've seen these in ProDemand. So weird that nothing comes close to what I got. Makes me wonder how much hackery occurred before it got to me.
Yes, and unfortunately SI isn't really clear because there are a half dozen variations of the vehicle. I did a google search for that specific vehicle and vacuum diagram and turned up this site for replacement hoses. parts.driveavw.com/p/Volkswagen… in the applications list it did have your vehicle. Its not a great picture but does your look like this? At lest it looked like the same…
That's a 2.0 diesel. I've seen many diagrams for the diesel. Very confusing. I think I finally got the right item. Even my dealer had to call someone on this.
I have a call into the dealer. They gave me this pic and a part number: 5C0612041H Google shows that line has a check valve right at the sensor. Guess the hacks cut it off completely. LOL. Thanks for your replies.
I looked it up by VIN and it shows you have this pipe.
Yes, that's the diagram my dealer finally came up with. Problem is that pipe is a far cry from what it actually looks like. Thanks for the help.