I’ve taken the BGB plunge to do a custom tune to get my Macan turbo running smoothly and will post full details when finished - but until then I thought id throw out the fact that v206 from Cobb is today out on the AP for those wanting to review it.
In doing all this I have a theory that for us turbo owners, the Cobb tune isn’t necessarily bad, but it might be the diverter valves - something that gets little press here so far.
So I’ll also start this thread to ask folks about an issue I believe I have relating to diverter valve leaks to see if others have seen this. Rather than try to describe it - I’ll post a link that shows it in all its ingloriousness below, albeit on a GTS.
Above is a link to my personal experience.
I believe mine are failing as I’ve experienced it more with every hope that the new Cobb map would fix the intermittent issues.
I did this video in seventh gear to show the boost dropping while the rpms stay steady/increase to show my foot is still on the throttle while not giving the PDK a gear to upshift into. Furthermore I believe that this happens in lower gears, but when it occurs, especially in the torquey turbos, the PDK interprets the torque drop as accelerator let off -meaning we are done trying to accelerate more aggressively and (erroneously) upshifts, especially in comfort mode which it probably does to get better gas mileage. If the boost then rebuilds or you apply more gas - the car gets confused at your intent and is what many turbo owners have complained about.
This boost drop still happens in sport mode under partial throttle around 2-3k rpms but the PDK is less eager to upshift so it’s currently less noticeable. It does NOT happen in WOT because the car is in lockdown mode where it interprets your input as “haul ass” and does so without intervention and sole goal to put the power down.
In light of this - I will have the diverter valves replaced ($600-$800 parts plus labor) and provide a before and after of both the Cobb OTS map and my custom tune (which currently does not exhibit the behavior and is the reason I sought it out) to hopefully give folks here the best advice on what to do if they experience the same.
As mentioned - I’m working with John at BGB on a custom tune - he has been phenomenal and worth every penny and my full review of this experience I’ll post once I’ve completed the process - but my guess is that part of the blame may fall on the diverters and more and more people may experience this with the higher boost levels of the Cobb tune.