sauceman101
Ready to race!
part number four in the diagram in this thread.
http://www.golfmk6.com/forums/showthread.php?t=23225
6
Loud screeching noise from engine bay
- Thread starter DaButcher
- Start date
part number four in the diagram in this thread.
http://www.golfmk6.com/forums/showthread.php?t=23225
mto386
Go Kart Newbie
If your car sounds exactly like my video its not the air pump....
sauceman101
Ready to race!
Exact same sound, as far as I can tell its coming from right under the vacuum pump which leads me to believe the kombi valve that my hose is running to. Not saying the pump is bad, but a gasket or hose broken in that system could cause a leaking noise like this
mto386
Go Kart Newbie
It's possible. I certainly thought that was the culprit at the time of the video. I was just telling mattsc, the air injection pump turns on and the kombi valve opens up only for the first few moments of a cold engine start up for emissions purposes. If you're hearing the noise on acceleration then it isn't the hose. To do a test you can unplug the air pump and kombi valve before a cold start.
sauceman101
Ready to race!
I'm also posting in this thread in this thread that is located in the General discussion. Seems to be similar.
http://www.golfmk6.com/forums/showthread.php?p=2335732&posted=1#post2335732
What is the easiest way to unplug the air pump and the kombi valve? just pull the little clips off the kombi and i would assume there are a few on the pump itself? Willing to try anything to figure this out
mto386
Go Kart Newbie
It's the same issue, lets keep it here since it belongs in this section. I believe the kombi valve has two plugs on/near it. Looks like one is for the valve and the other is fir the pressure the sensor. See picture below. There is another plug on the air pump too. If you're still getting the squealing then you know its after the valve. Start with the gasket. For those of you who dont have oil buildup around the valve start with checking around the manifold.
sauceman101
Ready to race!
^ second for continuing in the proper section. Hopefully I will be able to actually get at everything when I have the time tonight or tomorrow, in a brace from my palm to past my elbow on my right arm for three more weeks, this will be the first time i've tried to work on something with this thing on. Will swap out broken hose output hose between kombi valve and SAI pump as well as check the gasket if I can before I pull the intake and heat shield to check the exhaust manifold. I think this is the closest I've been to resolving this since the chase began!
sauceman101
Ready to race!
So Tuesday night I was able to replace my SAI pump to kombi valve hose, that eliminated my P0491 and P2440 codes, still have the P0420 code as well as the noise. Without taking the intake off looking from the side the exhaust bolt seems good, there's a little soot, but idk that it's what you dealt with. Didn't pull the kombi valve to check the gasket because it looked like something I only want to do once
mto386
Go Kart Newbie
Post the full size picture of the first one. It looks like there could be some but its so oily and dirty I can't compare. Can you pinpoint where the oil is coming from? My bolt snapped but it stayed in place with enough less tension to crack the gasket and there was no visual indication other than the soot. The kombi gasket is cheap so just replace it when you pull it. Does the sound disappear after a few moments after a cold start up or is it continuous?
sauceman101
Ready to race!
Here is the full size of that first pic, I was going to pull the intake and look with a mirror, but figured I had a good enough shot from here. If you think pulling the intake stage 2 piece and heat shield and looking in there with a mirror will get a better angle I can do that tonight. AS for the sound, it is on start up occasionally, lasts for a few seconds then goes away. It will come back randomly. The conditions it seems to come back in most often are after cruising in 5th or 6th at highway or freeway speeds for a few minutes and then exiting, the noise starts when I rev it after a long bit a steady RPM whether I rev it up with the clutch disengaged or engaged and accelerate. If I push the clutch in and run the RPMS up to 5 or 6k rpms it goes away and doesn't come back until I've driven under typical conditions above. Occasionally it occurs at random but that seems to be the most common way to replicate. The other way I've been able to replicate it is shut the car off for five to ten minutes after it being on for any amount of time. Coming back and starting it again and it's there on start up even if it wasn't the previous drive at start up. If I let it sit for an hour or two to cold start, it is completely random if I have the noise on startup.
Lastly, It appears that the oil is coming from that outside bit on the vacuum pump as oil sits in there, very heavy gunk that is visible in that third picture. But it seems it could also be coming from the kombi pump gasket. At this point I'm thinking that the oil leak and sound may be separate issues. I will order the gasket for the kombi pump next time I get something from ECS, probably in the near future, can't justify 7-8 dollar shipping on a 4 dollar gasket lol
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mto386
Go Kart Newbie
The reason why it could be a gasket issue is when the engine/manifold/valve heat up the metal expands making a tighter seal. When it cools it contracts and you'll get it again for the first few moments until the engine heats up. Of course high pressure will still get through and make a sound. When you're in neutral there is no load and no matter how high you rev so there will be no boost.
Pretty sure the part number is 06J131120B for the gasket. Go to your local VW/Audi dealership's website and order it for $3 and pick it up.
Pretty sure the part number is 06J131120B for the gasket. Go to your local VW/Audi dealership's website and order it for $3 and pick it up.
sauceman101
Ready to race!
Yea that is the part number for it, the noise will occur when the motor is in vacuum or when I'm in boost, that doesn't seem to matter
sauceman101
Ready to race!
quick update: haven't got the gasket yet, but I was off monday and tuesday hunting in Pennsyltucky, took the GTI instead of the truck anticipating some nice state park roads. After flogging it in the hills for ten to fifteen minutes straight, redline shifting in straight aways and proper downshifting to keep in power, the whistling/screeching noise stayed present for about 5 minutes of normal driving when gas throttle was applied. It didn't go away or "clear" with a neutral throttle stab to about 5k like it always does. I forgot that I did an auto-x last october when the noise started and it was relatively warm for mid october here in NJ. The noise persisted through ten runs as I had a buddy dual drive it. Could it have something to do with heat? if so I'd be very inclined to think the exhaust manifold is involved as it was for Geryon86. Anyone with thoughts or input?