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2017 GTi PP at VIR

Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
Folks I have no issue fostering healthy debate so we can all improve. Some of you know one another. I don’t expect folks to agree with me or the mod path I’ve chosen. I have learned a lot from the auto-x group and David’s thread. I prefer hanging out in the “track” section of the forum as there is less posturing and posing. I do not want Fan Boys A beating up on Fan Boys B. Healthy debate, I have no issue with.
I welcome anyone on my thread, all I ask is that we treat one another with RESPECT.
 

Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
I still need to check for boost leaks.
Going to check the waste gate calibration
I can’t verify AFR’s without data logging, so an Accessport may be in my future.

Id prefer not have to go through that expense, if I don’t have too.

In all the time I’ve tracked the GTi, this is the first time I’ve had fuel dilution this high.
Coincidence?
I’ve learned to investigate coincidences.
My troubleshooting list for the IS38 boost flutter:
1) Check for boost leaks (local tuning/track support shop says the had a similar boost flutter on a TTRS which had a boost leak)
2) Check waste gate calibration ( even if this is off, my understanding is that you would go into limp mode. Which didn’t happen but I want to eliminate it as a source)
3) APR IS38 tune is known for boost flutter ( I wasn’t aware that this was an issue- yes I live under rock if this is common knowledge)
4)AFR’s running lean - purchase Accessport and take some logs ( my understanding is that GTi fueling is adequate for an IS38 upgrade, even when tuned)
5)

I’m down on straight line speed, so something is off. Even if it’s common to see boost flutter with the IS38 and APR tune. I’d expect more top end down the straight. Cooling should not be an issues now so the engine shouldn’t be derating to compensate for heat.
 

tigeo

Autocross Champion
My troubleshooting list for the IS38 boost flutter:
1) Check for boost leaks (local tuning/track support shop says the had a similar boost flutter on a TTRS which had a boost leak)
2) Check waste gate calibration ( even if this is off, my understanding is that you would go into limp mode. Which didn’t happen but I want to eliminate it as a source)
3) APR IS38 tune is known for boost flutter ( I wasn’t aware that this was an issue- yes I live under rock if this is common knowledge)
4)AFR’s running lean - purchase Accessport and take some logs ( my understanding is that GTi fueling is adequate for an IS38 upgrade, even when tuned)
5)

I’m down on straight line speed, so something is off. Even if it’s common to see boost flutter with the IS38 and APR tune. I’d expect more top end down the straight. Cooling should not be an issues now so the engine shouldn’t be derating to compensate for heat.
Yes, APR's tunes can have some fluttering/surge under boost. The nature of high boost on these turbos sometimes, they just aren't always "in the zone" w/r to turbine speed/boost/RPM. I wouldn't honestly worry about it. I've read so many posts about it.

You can log with OBDEleven or VCDS - do you have either of those?

Just so I understand - why do you think you are running lean again? You are correct however, the IS38 is not an issue with stock fueling on the APR tune. Hell, my IS38 on my 1.8 doesn't have a fuelling issue. The tunes handle it.

Boost leaks are often determined from logging boost request vs. boost actual - if you have a leak it will present itself in the data. I don't see how thet boost leak would cause the lean condition - the ECU will just adjust to meet the requested lamda. You just will be down on power.
 

GTIfan99

Autocross Champion
Location
FL
lol. i lap you with no tune. These silly "i'm a bad ass and apr ain't shit" threads are retarded. Do you track your car? Nope. Have i seen you at VIR? Nope. Have i seen your car at Summit Point? Nope. Sorry for you bitch ass niggas, you don't have shit and you don't know how to drive. Fuck off.


I apologize for this outburst, im going through a difficult time and i should not allow it to come in here.


Have I seen you at Sebring? Nope. Have I seen you at Daytona? Nope. Have I seen you at Road Atlanta? Nope. Have I seen you at Reobling Road? Nope. Have I seen you at FIRM? Nope.

I wasn't aware that only those that go to VIR track their cars. Come on dude, I've seen maybe 5 VW's at track days in the last 5 years in the south east, that doesn't mean people up north, mid west, and out west don't track.

Again, I have no issue tracking the car with stock tune. I'm personally not a fan of APR's tunes, because they tend to use more boost that other tuners. And tracking or not, if you tune the car, you need to be able to log. I've been tracking, tuning and modding cars for 35 years. There are always variations car to car, and you can be the guy that has a bad O2 sensor off the lot. It's happened to me.

Sorry if you're having a rough time, I hope everything works out for you.
 
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Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
Yes, APR's tunes can have some fluttering/surge under boost. The nature of high boost on these turbos sometimes, they just aren't always "in the zone" w/r to turbine speed/boost/RPM. I wouldn't honestly worry about it. I've read so many posts about it.

You can log with OBDEleven or VCDS - do you have either of those?

Just so I understand - why do you think you are running lean again? You are correct however, the IS38 is not an issue with stock fueling on the APR tune. Hell, my IS38 on my 1.8 doesn't have a fuelling issue. The tunes handle it.

Boost leaks are often determined from logging boost request vs. boost actual - if you have a leak it will present itself in the data. I don't see how thet boost leak would cause the lean condition - the ECU will just adjust to meet the requested lamda. You just will be down on power.
Appreciate the feedback.
I do have an older OBD11. Just need to figure out how to log. I have used live values. Don’t recall seeing a log function, but then I was not looking for it either.
Will do a little research to figure out how to do it. Actual Boost vs. Requested Boost.

Don’t believe that I am running lean. It was listed as a potential root cause for the boost flutter/low power.

It appears that IS38 APR tunes have boost flutter, I’m trying to figure out why I’m slower down the straights. I see 38-39psi in third gear but in 4th gear it is much lower at 32psi. This is the first time I’m tracking the IS38 so have no base level to compare against other than my previously tuned IS20.
 

tigeo

Autocross Champion
Appreciate the feedback.
I do have an older OBD11. Just need to figure out how to log. I have used live values. Don’t recall seeing a log function, but then I was not looking for it either.
Will do a little research to figure out how to do it. Actual Boost vs. Requested Boost.

Don’t believe that I am running lean. It was listed as a potential root cause for the boost flutter/low power.

It appears that IS38 APR tunes have boost flutter, I’m trying to figure out why I’m slower down the straights. I see 38-39psi in third gear but in 4th gear it is much lower at 32psi. This is the first time I’m tracking the IS38 so have no base level to compare against other than my previously tuned IS20.
It just so happens that I am an expert on all matters OBDEleven. You can see how to log in my video on my YouTube channel:

logging with OBDEleven - YouTube
 

tigeo

Autocross Champion
Here's a question for the track rats....brake fluid. I bled/flushed my system about 4 weeks ago when I installed my BBK with Motul RBF600 fluid. I'll be at VIR in a few weeks - am I good or do I need to do it again? I've put just shy of 2.5K miles on it since then (1K of it was a highway trip).
 

GTIfan99

Autocross Champion
Location
FL
I'm using 660, which seems to attract more moisture in humid climates and need more frequent bleeding. I've never had issues with 600. You should be fine, but a quick bleed prior to an event is always a good idea.
 

Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
It just so happens that I am an expert on all matters OBDEleven. You can see how to log in my video on my YouTube channel:

logging with OBDEleven - YouTube
Thank you for this. Going to use it tomorrow. I want to get my front Verkline LCAs installed but need to get this issue resolve first. Datalogging will help narrow things down.
 

Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
Here's a question for the track rats....brake fluid. I bled/flushed my system about 4 weeks ago when I installed my BBK with Motul RBF600 fluid. I'll be at VIR in a few weeks - am I good or do I need to do it again? I've put just shy of 2.5K miles on it since then (1K of it was a highway trip).
I would do a quick bleed to make sure you have all the air out the system. The last 2500 miles would have shaken the last few bubbles out. No need to flush the fluid.

I will be back at VIR for the Audi event.
 

daconchslop

Autocross Champion
Location
South Carolina
4)AFR’s running lean - purchase Accessport and take some logs ( my understanding is that GTi fueling is adequate for an IS38 upgrade, even when tuned)
Unless you’re planning to ditch the APR tune for a Cobb tune/r don’t purchase an AP just to log AFR’s.
Probably unable to log an APR file with an AP anyway..unsure about that.
 

tigeo

Autocross Champion
I would do a quick bleed to make sure you have all the air out the system. The last 2500 miles would have shaken the last few bubbles out. No need to flush the fluid.

I will be back at VIR for the Audi event.
Ok cool! What group are you running with?
 

Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
I’m in black with Audi.
 

Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
Unless you’re planning to ditch the APR tune for a Cobb tune/r don’t purchase an AP just to log AFR’s.
Probably unable to log an APR file with an AP anyway..unsure about that.
Not yet.
Going to use my OBD11 to log. Need to figure out why I’m down on power.

I’m on a time crunch to be able dial in a custom protune before my next event.
 

Mini7

Autocross Champion
Location
Charlotte, NC
Car(s)
2017 GTi Sport PP
IS38 Wastegate Voltage

I’m in Engine/Live Values

Is charge pressure actuator, acknowledgment the right parameter I’m looking for?
When I watch the DAP video he selects Charge air pressure control valve unconditional voltage sensor. I cannot find that on my OBD11.


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