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Chasin' Another Boost Leak?

MSH

Drag Racing Champion
Location
Denver
Car(s)
'20 M2 Competition
Assume this is just another small boost leak I get to chase? No CEL's at all or codes on my Accessport.
I always keep my Accessport hooked up and just noticed that I didn't seem to be hitting my typical 33-34psi peak, so pulled a log.

https://datazap.me/u/msh/chasin-another-boost-leak?log=0&data=3-5-24-28-30-31-32


Screen Shot 2022-09-21 at 10.20.36 PM.png
 

MSH

Drag Racing Champion
Location
Denver
Car(s)
'20 M2 Competition
That is their default list. All I ever use. I just removed a bunch of columns. I’ll post up the full list later thx
 

Superfreak

Autocross Champion
Location
Denver
Car(s)
‘19 M2C, ‘05 Taco
Love to see different data but I was coming up short in identifying the data indicating boost leak. Were you comparing target boost pressure to relative manifold pressure? Or was it turbine base vs. final value? Apologies for the ignorance, I’m still trying to learn what data to look at. I don’t know that I’d be able to see if I had a leak other than to look at prior boost values.
 
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Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI
This is the PUT and the MAP sensor actual readings. At WOT you'll see very minor differences. Everything looks ok here indicating no boost leak back in March, post intercooler readings.

https://datazap.me/u/msh/log-1647110450?log=0&data=8-15-38

Pre-intercooler is a bit more difficult as there is nothing you could log showing pressure at the turbo outlet. This is where looking at PUT setpoint vs PUT actual helps out. As you can see it is hitting the request back in March.

https://datazap.me/u/msh/log-1647110450?log=0&data=8-15-42

Now that doesn't mean it doesn't have a boost leak. If you're targeting say 25psi on a Vortex and the WG is closed the entire time you probably have a boost leak or a bad turbo.

You also have to look at the WG% to see how much duty it's taking to hit that boost level. In this case it's pretty high, but you guys are up in Denver and this is a lot of boost. Not surprising values.

In the latest log you will see that the WG is fully shut and it is also not hitting target boost (we assume, we can't see the PUT sensor actual).

https://datazap.me/u/msh/chasin-another-boost-leak?log=0&data=31-32-33

Now, this COULD be a boost leak, but also remember the ECU can only see that it has commanded the actuator shut and that the voltage applied should be forcing the flap to shut. If the internal spring to the actuator has grown tired and while it thinks the flap is shut it is physically unable to counteract the exhaust volume. But if that were the case you typically would see the WG% flapping around trying to modulate boost. I'm guessing since he said "another boost leak" and that this was pretty immediate happening that it probably is a boost leak. Or the turbo has finally had enough. Hoping for the former.
 

MSH

Drag Racing Champion
Location
Denver
Car(s)
'20 M2 Competition
Love to see different data but I was coming up short in identifying the data indicating boost leak. Were you comparing target boost pressure to relative manifold pressure? Or was it turbine base vs. final value? Apologies for the ignorance, I’m still trying to learn what data to look at. I don’t know that I’d be able to see if I had a leak other than to look at prior boost values.
Screen Shot 2022-09-22 at 1.59.38 PM.png


@Diggs24 - thank you so much for the detail/knowledge. I really appreciate you chiming in to help. I'm going to grab a 4th gear log here in a bit as the log I posted on the original post was a 3rd-4th log.

@Superfreak - I was comparing Target Boost vs Relative Manifold PSI, as well as, Turbine Act Base Value % vs Final Value. Maybe my understanding is off/incorrect but I always thought when comparing each of those sets of data that the values should align fairly closely once you spool up and hit target boost through redline. The above screen shot is when I did my final pull for Ed at EQT on my 5th revision for my E40 tune last February. You see that all the data aligns nicely...Relative Manifold psi and Target boost psi are close to the same and turbine base vs fianl are close to the same. I **thought** turbine act final value was synonomous with WG% but maybe i'm off there to lol.

When you compare those nicely aligned #'s above with my latest pull its not so good. The issue with the pull I did yesterday is it was a 3rd to 4th pull vs the 4th only pull that Ed/EQT has you do when tuning. To get an apples to apples I'm going to go out and do a 4th gear log in another hour or so and I will repost.
 

MSH

Drag Racing Champion
Location
Denver
Car(s)
'20 M2 Competition
Why not just give the boost pipes a gander first?
Yup that’s the plan. That was issue on first go around with this. I have v1 IE IC and apparently people running higher boost have had issues w them blowing off. Replaced my drivers side ic hose clamp with t-bolt last time I had a leak and it’s been working good thus far
 

MSH

Drag Racing Champion
Location
Denver
Car(s)
'20 M2 Competition
Screen Shot 2022-09-22 at 10.02.08 PM.png


Update - Well the t-bolt on the left (IE v1 worm clamp on right) had been holding great for the past 2.5 months or so. I thought the new one had completely solved the issue but I guess not. Like last time the hose hasn't completely blown off but one side is definitely slipping. I feel like it's a band-aid approach but going to try the hairspray trick this time and if that doesn't work EQT has suggested constant tension clamps vs the t-bolts. Unfortunately, these v1 IE ICs just sound like they are more prone to this issue
 

MSH

Drag Racing Champion
Location
Denver
Car(s)
'20 M2 Competition
Make sure the silicone pipe is oriented straight towards the IC inlet. If it's at even a slight angle it won't hold. Also, if you've had some blowby it will also tend to get oily there and exacerbate the issue.

Ok will do. You think this may be an issue? :unsure:

Called IE and they no longer offer hoses for the V1 IC. You (or anyone else) got a bead on a good place to order a new (stronger/durable) boost hose? Since it's the older style its 2.75" IC side to 2.5" charge pipe side

1663954002982.png
 
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