MK6 GTI boost drop issue

[Ghostmk6.1]

Alright so I’ve been having this issue for a long time with my car where my boost will peak, hit 0 and then build again. The car has had a K04 for less than a year, since January to be specific and I’ve taken it to multiple shops without any success of solving the issue, used a Rev D diverter valve, GFB and now a Turbosmart DV and issue still persists. Changed both fuel pumps, fuel filter, got my injectors tested and cleaned after a manifold swap and carbon cleaning, N75 valve, Multiple smoke and pressure tests. New coils, plugs, the list just keeps on going. And honestly I’m just sick of not being able to use this car at its full potential . I have a datalog if someone wants to look at it, If anyone on here could help me out I would be really grateful tbh. I’ll add the datalog below. (I apologize if it’s bad I have never posted on a forum like this so)

 

[uglybastard]

To me this screams boost leak. Do you have upgraded pipes on intercooler? Or a FMIC? Or throttle body pipe?

can you check clamps and face ups of piping and try logging again?

 

[Ghostmk6.1]

To me this screams boost leak. Do you have upgraded pipes on intercooler? Or a FMIC? Or throttle body pipe?

can you check clamps and face ups of piping and try logging again?

Yes I have an ARM FMIC, I changed the clamps that came with it for some better ones as I did not like the quality of the original ones out of the box. CTS Throttle body pipe and turbo outlet pipes as well, that all got done with my turbo install. I can check again tomorrow and get you a log

 

[Ghostmk6.1]

Alright, went under the car and also removed my front bumper and got this datalog. Not the best at reading them so hope someone can look at it and tell me what’s going on.

 

[TroyBoy]

Check the other end close to the turbo, where the CTS pipe connects. I had a helluva time with mine, also CTS TOP/K04.
I ended up just replacing the CTS back to stock pancake Pipe for reliability. In my case the Turbo Outlet Pipe would eventually come lose from the silicone turbo elbow.

 

[jay745]

Regular t bolts are garbage and you'll have issues with it popping off. Replace with constant tension clamps

 

[Ghostmk6.1]

Check the other end close to the turbo, where the CTS pipe connects. I had a helluva time with mine, also CTS TOP/K04.
I ended up just replacing the CTS back to stock pancake Pipe for reliability. In my case the Turbo Outlet Pipe would eventually come lose from the silicone turbo elbow.

I did the same because I had the CTS TOP installed but same issue with both stock and CTS.

 

[TroyBoy]

Sorry to hear but the validation feels good. I knew I could not be the only one. When I reverted to stock I thought all good, but I had not cinched it up properly and again it blew. So I got under the car, removed all pipes from the turbo to the IC and took my time, SOLID as a rock now.

I still plan to remedy and put the CTS TOP back on but with a custom "elbow" or a joiner as the APR is just too short. Maybe it is attributed to the CTS design I am not sure

 

[Grabbit]

I forget, can you post the data log as a .csv or excel file? Might want to try a Tunezilla link so its easier to read.

From what I can make out in the picture your waste gate duty cycle drops (which cuts boost) when the actual load and target boost is high. This means the ECU is pulling boost for some reason. What tune are you running? Has it always done this?

 

[uglybastard]

I forget, can you post the data log as a .csv or excel file? Might want to try a Tunezilla link so its easier to read.

From what I can make out in the picture your waste gate duty cycle drops (which cuts boost) when the actual load and target boost is high. This means the ECU is pulling boost for some reason. What tune are you running? Has it always done this?

Try datazap for your log

 

[Ghostmk6.1]

I forget, can you post the data log as a .csv or excel file? Might want to try a Tunezilla link so its easier to read.

From what I can make out in the picture your waste gate duty cycle drops (which cuts boost) when the actual load and target boost is high. This means the ECU is pulling boost for some reason. What tune are you running? Has it always done this?

https://datazap.me/u/darkmk6/datalog?log=0&data=4-22

I apologize for the late reply as I have been really busy and haven’t been able to work on the car or even look at this forum. But getting back to you, yes I’ve had this issue for a very long time. Sometimes the car won’t cut boost sometimes it will. Try using the link I provided maybe you could give me more insight through there

 

[Grabbit]

Nothing is really standing out to me but what is clear is that the WGDC drops from 75% to 2% at about 3100rpm. This is commanded by the ECU so I would check with your tuner if they have any thoughts. The drop from the low 90% to 66% just 300 rpm prior also looks a bit funky.

 

[Ghostmk6.1]

View attachment 271724

Nothing is really standing out to me but what is clear is that the WGDC drops from 75% to 2% at about 3100rpm. This is commanded by the ECU so I would check with your tuner if they have any thoughts. The drop from the low 90% to 66% just 300 rpm prior also looks a bit funky.

View attachment 271726

Thank you for looking at it, I asked him about this a long time ago and I never got a reply but I guess it’s worth asking again or maybe even looking into a different tuner :/

 

[Grabbit]

^ I had a somewhat similar experience with the IE K04 tune. I thought it was hardware or a boost leak, I threw parts at it until finally switching tunes to APR and the issue went away. Its too bad because when the IE tune was working in the beginning, it was better in my opinion. Had more low end punch. GL ...

 

[Ghostmk6.1]

Little update for everyone. Been running boost leak tests by pressurizing the system and spraying soapy water and can’t find anything :/
Also checked my Wastegate and from what I saw nothings getting caught there. Also heard of someone having an issue bc of their Maf. Unplugged mine to see if it would run better and same results :/