Lately ive been working on refining my k24 file for my a6. I have run into an issue with my throttle plate going from 100% to 50% as i crossover 4,000 rpms. This is right at where im ramping up my boost. Its not overboost, i dont think its torque monitoring.  Ive attached a log of a 2nd gear and partial 3rd gear pull. Any help is much appreciated this has been hanging me up for a while.

srm k24 turbos
gt500 inj
551r file
5120

throttle cut because your wgdc is at zero and you are still over boosting.

Your wgs are WAY too tight, your n75 is busted, your wg line is busted, or your wg is stuck closed. Or you are running an MBC lol.

They crack at 15 psi. ive only got ldrxn set for about 17 peak so i guess i need to crank the requested up a little and that should help. It threw me off that it starts to close before actual exceeds requested but i guess the pid knows its going to overshoot. Thanks for the help this rules out alot for me and just leaves managing boost and it should get sorted.



fukenbroken - what makes you think its not 5120? ive gone in and adjusted the constants in the .ecu file for the log so everything doesnt look off in that respect.

I spent some more time analyzing and i think i have a theory on whats going on if anyone can lend some input.
It appears that my rlsol flattens out right as the throttle cut occurs. Im trying to run beyond what that limit showed in ecuxplot
the solution here is more load request out of IOP/IRL correct? Im going to try a little higher IRL value and see if that has an impact.
please see image.


if thats not correct the other thing i was worried about was WDKUDGN trying to manage the throttle body below wastegate cracking pressure. I dont believe thats the case because it doesnt sort itself out once i get past wg crack pressure. the TB stays stuck at 50 for the whole pull

If i felt safer about the tune and sent it to 22 psi at 4500 ish i feel like id make some headroom for the wastegate to actually reduce boost levels generated. Its kinda mayhem trying to run boost at cracking pressure levels. Thats what im going to go for next.

This issue has postponed development of my tune. Initially i thought i was over boosting so i was reducing duty cycle. Part of the overboost you see is in response to the throttle plate starting to close. when that happens the map sensor upstream of the throttle body sees an increase in backpressure because of the restriction. As the throttle still stays closed i still have a back pressure there and a skewed boost reading from what itd be with the TB open.

You seem to think more mechanical issue with my WG. I was thinking its caused by boost being less than wg pressure to relieve boost levels.

thats insight i was looking for. it gives me something to work on. Ill up the boost curve a little and try and clean up WGDC. ill keep an eye on rlsol too. Thank you for your patience and persistence to help.