Please read this DIY in it's entirety before starting this project. I describe issues I had along the way, and issues you may have that I did not.
I do not recommend doing this diy if your car is running normal, and acheiving the average boost pressure of ~20psi. This modification is designed to regain lost boost, not acheive extra power on a properly functioning car. You do this procedure at your own risk, and I cannot be blamed.
For full details on symptoms, brainstorming, and all communication that happened to get us to this point, and figure out this issue can be found HERE. It is kind of a long read, but I highly recommend reading that first, before doing anything, if you feel you are losing boost for no reason.
Brief description of the issue this fixes:
Several of us found that we were losing boost for no reason. Stage 2 cars acheiving only 15psi peak on average, having trouble acheiving high boost numbers in low gears, boost taking too long to build, and not holding. Seems like it has become a fairly common problem among higher mileage 2.0tfsi cars. The DIY that this DIY is based upon can be found HERE. Many thanks go out to CiDirkona from golfmkv.com. I decided to make a more user friendly version, based upon our transversely mounted engines, and upon my experiences learning through this myself.
First, you have to create a tool used to complete this project. Don't worry, it's cheap and easy, but takes all day to dry. Just like your mom. OH!
Purpose of This Tool
The purpose of this tool is to be able to fill up the wastegate with air, while also being able to control the
amount of pressure being added to the system, and retain that pressure as well. The tire valve stem
allows mono-directional travel of the air. A bike pump can easily be used for best control of the amount
of pressure being used. An air compressor can be used, but you would not want to use more pressure
than the system is intended for (+- 15psi.)
Tools Needed
Drill with various drill bits
Dremel tool
rubber gloves
Plumber's tape
Silicon sealant
JB Weld
Parts Needed
1 1/4" PVC threaded cap[size]
1 1/4" PVC threaded plug
3' rubber vacuum hose
3/16" vacuum hose connector
Tire valve stem
Everything purchased above was either found at Lowe's or Oreilley's. Total cost ~$35
I forgot to throw the plumber's tape in the picture. lol.
First thing to do is attach the valve stem to the PVC plug. I measured the width of the valve stem and drilled a hole
smaller than that. Then with the Dremel tool, I slowly sanded the hole larger while test fitting often. The PVC was
actually a little too thick for the valve stem, and had to be sanded down in thickness as well. Then it just snapped
in perfectly. Actually better than expected.
Sidenote: I believe there are valve stems that mount with nuts and washers, which would probably be better in this
circumstance, but I didn't see them, and these were cheap, and worked fine.
I then sealed the inside around the valve stem with the silicon sealant just for added peace of mind that I did this
right the first time. I consider this an optional step, but did not test the pressure holding ability before the silicon.
Your call here.
Now, the vacuum tube connector is 3/16", so I would drill a 3/16" hole and voila! But alas, that was the only size
drill bit I was missing, so I went smaller and worked it around in circles til I reached the size I needed. I also cut a
groove straight across the center of the hole for the tabs to fit in.
Pop the connector in the hole, and JB Weld it on top and on bottom.
Let those dry overnight, plumbers tape the shit out of the threaded end, screw them together, and with any
luck, we have an air tight air tool to work on our wastegate.
Tools Needed
pliers
small stubby flatheat screwdriver
long flathead screwdriver
bicycle pump
tool made in previous section
jack stands
10 mm wrench
small hose clamp
First, we will start with where we attach our new tool to the wastegate actuator. You need to remove your air intake "ram air".
You will be in this area a lot. Here is what you are looking at:
At the end of the actuator is a nipple connected to a hose. air pressure fills this can and moves the rod back and forth, opening
and closing your wastegate. You need to get the clamp off, which as far as I know can only be done by mutilating it with pliers.
This is where you will need the small hose clamp later.
Once the clamp is broken and removed, the hose is sill stuck on pretty good, and a pull won't do it. I had to push it off with the long
flathead to get it off the nipple. This is now where you attach your new tool.
It is easiest to attach the vacuum hose from the top, and then drop the pvc down between the engine and the bumper so you have
access to it from underneath. The rest of the work is done on your back.
You will first have to remove the underbelly tray. If you can't figure out how to do this, please stop now.
From underneath the car, find the same actuator can. The rod we are adjusting connects to it, and points towards the back of the car.
First, with the long flathead, you must snap this clip off. You will not be replacing this clip. It is kinda just held there by spring-like
pressure, and what looks like a brown, OEM-type lock-tite. just pry it off, and it will come off pretty easy.
Once the clip is removed, you will need to break the locking nut free from the lock-tite. It is fine to move the lock nut without adding
pressure to the system with the pump. Twist it towards the front bumper, away from the adjustment nut. Now is the tricky part. You
must add pressure to the system now with the pump, to take pressure off the adjustment nut. This takes finesse, as you have to keep
varying the pressure by pumping and releasing. Take care not to add more pressure to the system than it is inteded for. Only one
pump of my pump created almost 20psi.
Do not move the lock nut further than you want to adjust the other nut. I could not see a way that you can retighten the
adjustment nut. Because the way it is built, I do not know of a tool you could use here, all you can use is your hand on the
adjustment nut, and I could not screw it the opposite way. This being said, take care that you don't over do it. I could not
honestly tell you how many full turns of the nut I acheived, but I did this whole procedure three different times, so that I wouldn't
over do it. There may be a tool that can reach up there, but I don't even know what it would look like.
When you have the adjustment nut where you wanted it, lock the lock nut back up against it, replace the hose on the end of the
actuator can, and lock it down with the small hose clamp. This is where I needed the little stubby flathead. There is very little
space between the fan and this spot, so just take your time and make sure you get that clamp on tight.
Last edited by jimrobbington; 03-27-2011 at 09:18 AM.
Before I did this adjustment, at Stage 2, I was only seeing a peak boost of 15psi in a third gear run, tapering down to 10psi.
Third gear pull from before I attempted any adjustment:
After this mod, I was able to hit 18psi, tapering down to about 13psi
Third gear pull after third adjustment:
A problem I came across, is that the adjustment nut got stuck, and I could no longer move it by hand. I believe the reason that it got stuck is the OEM lock-tite on the threaded rod was possibly too thick, and the adjustment nut is stuck on this. I cannot apply enough pressure on the adjustment nut by hand to move it. You may want to use a small wire brush to try to remove this from the threads before proceeding.
Last edited by jimrobbington; 03-28-2011 at 08:44 AM.
that was a great write up, and i only have two questions,
- the adjustment nut can be unscrewed with your hand, but cannot be screwed back on with your hand is what i understood from your second to last paragraph.....is it impossible to screw back on? or is it just such that human hands would have a hard time turning it back/its in an awkward position....all im getting at is im wondering if you could use a very very very tiny monkey wrench to be able to tighten that up?
- the last paragraph you mention using a small hose clamp.....i have a forge dv and i secured my hoses with zip-ties.....would you think a zip tie would be able to keep the vacumn tubing on?
I do believe that you can tighten the adjustment nut back, but not by hand. It is in such a space that only the side of one finger can roll along the nut, you cannot get your thumb on it to get any grip. There is abracket built around the nut, such that you cannot get your average pliers on it, plus it is round with grooves, and not shaped like a nut at all.
Zip ties may work, because I don't think this hose sees too much pressure, but I'd rather be safe than sorry. If that hose comes off, you have no wastegate control, and I don't know if the car would die, over boost, or explode.
Originally Posted by Coderedpl
Can you boost to 20 in city driving? Do a second gear pull and see if it hits 20. If it does then good. What i'm worried about for myself is that i'm already boosting to 19-20 on highway...........if i adjust, will i boost to like 25?
I dont want the next thread from me to be "I'm stumped......blown turbo, now what?"
Codered: NO, I cannot hit 20psi in 2nd gear. It has actually leveled out from the first pull, and it appears 19psi is my highest number. I can hit about 18psi in EVERY gear, which is so much more than I'm used to. It actually feels, though that second gear improved, but the other gears seem to have improved more (talking acceleration). But there is only a 1-2 psi difference between peak in every gear, whereas before, 1st gear's peak was 12, now it's 18. Third gear's peak was 15, now 18. Fourth gear's was 16, now 19. So it seems as though not only have I acheived ~3psi more across the board, 1st gear is seeing power it never had before. I strongly believe that if I could get the adjustment nut past where I am at now, I could get it up to 20psi across all gears.
Judging from your before and after videos, it looks almost exacly like the before and after of when I had my cam/follower/pump replaced under warranty.
I used to be having a real hard time getting boost and staying there, now that the repair has been done it looks more like that video, are you absolutelly certain that the cause for your low boost was only the WG?
And if so, say I have a peak boost of about 19 and hold to about 17, would ajusting my WG rod give me more safe boost?
Sorry I never saw the question above for some reason. To be sure, it was never something wrong with my hpfp.
After wastegate adjustment, and small maintenance issues here and there, I have amazing turbo response. I can boost up to 19-20 psi in 1st and 2nd, 23 psi in 3rd, and up about 1 psi each gear. Max I have seen is 26 psi in high gears. Boost is completely reliable, and I can always achieve max boost, given the proper conditions.
I will be running boost logs in about a week just for fun, but I have literally had 0 ill effects from this mod. I am still very happy with my results. The stock turbo has impressed me with what it can handle. Will post logs when I get them.
Lol! Totally forgot to post them in here! Doh! I have them at home in xcel sheet form. I will post it up later today if i remember again!
The crazy thing is, my tune is actually requesting 24 psi at some points, so my actual boost is right in line with requested. I was very surprised to see requested so high. My Revo boost is set at 7, I think 6 is recommended for stage 2.
So check this out. I added the fuel rail pressure as well so that you could see how my shitty 116 bar PRV dumps fuel almost as soon as I build full Boost. So I'm thinking I will be able to hold peak boost for a few hundred more RPM when I upgrade that.
you wanna use my stock prv until you get one of johns? mine was holding 130bar easy. my graphs are in that fuel pressure relief valve thread if you want to see em
you wanna use my stock prv until you get one of johns? mine was holding 130bar easy. my graphs are in that fuel pressure relief valve thread if you want to see em
Yeah, that would be awesome! I don't need anything bigger until I can afford a hpfp anyway, lol. Yours did hold remarkably well.
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