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Wastegate flapper not closing fully

snowmon

Passed Driver's Ed
Location
US
Car(s)
MK7.5 GTI S
OK, so first off, I couldn't unhook the DP as it snowed here where I live but I used a telescopic mirror to look at the wastegate arm from the top of the engine bay. The first screenshot shows me trying to run the "position test of end stops of charge pressure actuator" I pressed and held the green confirm button at the bottom right corner and it started the test. I heard what sounded like a motor trying to run, but mechanically nothing moved at the wastegate flapper side. After about 10 - 15 secs I got a message on the OBDEleven saying "Abort for safety reasons" Also if you notice, "position test of end stops of charge pressure actuator" says "not available" Does this mean my OBDEleven doesn't have this testing feature? The second screenshot shows the wastegate live data with the engine running in idle, do the numbers look right to you guys?

Screenshot_20230201_121303_OBDeleven VAG.jpgScreenshot_20230201_123028_OBDeleven VAG.jpg
 

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI
It means it tried to close it and couldn't so it aborted. You'll have to cycle the car and OBD11 to try it again. Try it again and watch the voltage.

At this point you should probably disconnect the arm from the flapper completely and see if it can physically close at all. That will determine if it's a flapper issue or wastegate issue. I'm still leaning toward bad wastegate.
 

snowmon

Passed Driver's Ed
Location
US
Car(s)
MK7.5 GTI S
It means it tried to close it and couldn't so it aborted. You'll have to cycle the car and OBD11 to try it again. Try it again and watch the voltage.

At this point you should probably disconnect the arm from the flapper completely and see if it can physically close at all. That will determine if it's a flapper issue or wastegate issue. I'm still leaning toward bad wastegate.

When you try it again and watch voltage it should hit these, it will hit lower then move to upper pretty quickly.

View attachment 271943

Great troubleshooting tips, thanks, Diggs! I will try this first thing in the morning
 

snowmon

Passed Driver's Ed
Location
US
Car(s)
MK7.5 GTI S
It means it tried to close it and couldn't so it aborted. You'll have to cycle the car and OBD11 to try it again. Try it again and watch the voltage.

At this point you should probably disconnect the arm from the flapper completely and see if it can physically close at all. That will determine if it's a flapper issue or wastegate issue. I'm still leaning toward bad wastegate.

So I finally got to do some troubleshooting this weekend. I had to completely take the downpipe and the mid-pipe off because mine had a differential totally blocking the way. So as you've suggested I disconnected the actuator arm from the flapper and I was able to physically move the flapper shut with my hand so I knew it wasn't the issue with the flapper side.
So fast forward, I had already ordered a new actuator which I received a few days ago, and replaced it, but I'm having a hard time running the first adaptation. Cycle key was on with the engine not running, checked the charge pressure acknowledgment voltage which was 4.67v initially. I went under the car and tightened the arm and lowered that voltage to 3.55v and ran "First adaptation of charge pressure actuator" and all it says is "Basics settings ended" then right below it says "Not available" So I did some research and found your advice on other members about IS20 adaptation:

"Clear all codes
pull up adaptation first setting and see voltage data
manually move wastegate arm linkage so it reads 2.1x volts, it's tight but it moves
run end stops test, pull up upper and lower and charge pressure acknolwdgement to see voltage data
see if it hits 3.5x V, doesnt need to run full test, abort wwhen it goes to look at lower voltage
cycle key off
cycle vcds

lather rinse repeat"

So following your steps I wasn't sure what you meant by manually move wastegate arm so it reads 2.1v, do you mean I use my hand to push the arm towards the actuator so that the voltage will go down? I'm starting to wonder if it's even possible to use OBDEleven to do adaptation at this point
 

snowmon

Passed Driver's Ed
Location
US
Car(s)
MK7.5 GTI S
How does it perform? Makes target boost?
Sorry for the late reply, I have work today so I had to sleep early :cautious:
It's doing the same thing where the boost builds up to 6.5 to 6.9psi, falls below 1psi, and builds boost again. The difference, however, is that it feels like the turbo spools faster than before. So it feels like I fixed a part of the issue I'm having, I say this because now my flapper stays completely shut when the engine is idle and there is no more exhaust fume inside the cabin. I feel like I've had multiple boost leak issues and missed something, I'm thinking of redoing the boost leak test. Just out of curiosity, can a leaking rear main seal also cause this sort of boost leak problem?
 

snowmon

Passed Driver's Ed
Location
US
Car(s)
MK7.5 GTI S

This is what it does after I run the wastegate adaptation with a cycle key on position, and the engine not running. I don't get any error messages or anything so I'm not sure if this means the voltage was set or not. I've seen guides on adaptation for VCDS which clearly says "Finished correctly" but OBDEleven is finicky, never sure if something is done correctly or not on this interface

Screenshot_20230217_190758_OBDeleven VAG.jpg


Then when the engine is running and the car starts moving, this is what it looks like. The voltage was set at 3.55v but it changes to 3.511v when the car is moving.

Screenshot_20230217_190850_OBDeleven VAG.jpg
 
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