RhinoComp

The nut holding the steering wheel probably giggles a bit more also

Defratos

lol are you being sarcastic?

Defratos

Also is this the right link to buying the tune for the GTS---> https://www.softronicsoftware.com/ca...oftware-10-17/

jpru2001

For a 958.2 you want this one: https://www.softronicsoftware.com/ca...nnett-v8-2015/

If you got an NA 958.1 I wouldn't spend money tuning 25 HP out of it.

Defratos

Thanks mate, no mine is a GTS so hope to get something decent out of the TT V6.

Now I'm just trying to understand what kind of battery I have to hook up the car battery to while doing the tune read and write procedure.

Does anyone have a pic of how a 40amp charger looks like (as stated by the OP) when I google it all I get are chargers for EV cars.

BrendonSF

Here's one: https://www.autozone.com/test-scan-a...B&gclsrc=aw.ds

RhinoComp

Yep just a joke, but I’d imagine the real results are similar! If I get tempted over the edge, I may find out for sure

Defratos

lol thanks for the help guys and calrification Rhino

wcpfour

Not sure how I missed this thread when I got my tune a few months ago... John at Soul made me a deal when I got my bypass pipes, and I'm happy he did! Love the tune, performance is silly now. But I do have a couple of boost flutters / cutoffs that are annoying and wondering if my diverter valves may be the issue. I have a '17 958.2 'S' with about 68k miles and did the tune just a few months ago at 65k. Occasionally I get a surging when accelerating through the middle of the RPM band. Also, I just noticed when driving over the Rockies through Utah and into Denver over the weekend that partial throttle under load the boost will cut off abruptly and then boost again repeatedly. Noticed this mostly in higher gears at highway speed on continuous inclines in the mountains. It wants to boost to keep speed up the hill, but then it cuts boost and boosts again.

For reference, I see a max at 17psi, with the fluctuations happening around 10-12psi before dropping back to low single digits or zero.

How are the diverter valves to replace? Did you just replace with the stock part or is there an upgrade option out there?

RhinoComp

That boost cut/power loss you're feeling is actually most likely due to oversensitive knock sensors. This affects pretty much all 958.2 V6TT Cayenne S and GTS models and is remedied by a dealer visit to address the oversensitive knock sensors with an update to the DME. It's talked about extensively in this thread: 2016-2017 Cayenne GTS Loss of Power

I had this fix done on mine a couple of months ago and it has solved everything like what you've described, and my car actually gets the fuel mileage it's EPA rated for now too, which it never could before even with trying as hard as possible. I would hypermile and couldn't get a full tank to average above 22mpg on my S, now I've had a full tank average of 25 once or twice. It's also worth printing out the actual technical service bulletin below as many have reported that their dealer isn't familiar with it off the top of their head. My service advisors weren't familiar with it, but when I brought them this printout they took it to the service manager who had remembered it from years ago (this has been out since late 2017 I believe).



Linked from the original thread for ease

wcpfour

[QUOTE=RhinoComp;18869625]That boost cut/power loss you're feeling is actually most likely due to oversensitive knock sensors. This affects pretty much all 958.2 V6TT Cayenne S and GTS models and is remedied by a dealer visit to address the oversensitive knock sensors with an update to the DME. It's talked about extensively in this thread: 2016-2017 Cayenne GTS Loss of Power

I had this fix done on mine a couple of months ago and it has solved everything like what you've described, and my car actually gets the fuel mileage it's EPA rated for now too, which it never could before even with trying as hard as possible. I would hypermile and couldn't get a full tank to average above 22mpg on my S, now I've had a full tank average of 25 once or twice. It's also worth printing out the actual technical service bulletin below as many have reported that their dealer isn't familiar with it off the top of their head. My service advisors weren't familiar with it, but when I brought them this printout they took it to the service manager who had remembered it from years ago (this has been out since late 2017 I believe).[/QUOTE

I read through the description of that issue, but I'm not actually having any power loss. I bought mine last Sept. as a CPO, installed the Softronic tune in March this year. I've driven this same route from LA to Denver with and without the tune, and I did not have the issue before the tune. I'm not losing power, just seeing the boost build and then drop repeatedly with a steady throttle (does it with the cruise control on) and just get a little surge but never lose power or speed. I can feed it more throttle and the issue goes away. The other conditions where I get some boost surge is full throttle, usually in 2nd gear when it just surges with no drop in the boost (at least on the digital boost "gauge"). Otherwise, power and performance feels fine.

RhinoComp

[QUOTE=wcpfour;18869656]"Power loss" is kinda misleading, it's just the way it was worded several years ago. Even before the fix, I could give it more gas and get full power or enough to get around anyway. My issues were exactly those you're describing, especially loss of boost while in cruise control.Boost cutting out in cruise control and partial throttle is by far the most prevalent and unique symptom of the software issue. My car had only done it moderately enough for me to kinda notice I would lose speed occasionally (in the realm of 2-3mph) when going up hills or the mountain pass near me, but it wasn't until I took a longer trip to Montana that I noticed after a longer drive that I could lose 10mph while I was on cruise control before I would have to step on the gas and drop down to 5th or even 4th gear just to build boost and be able to get back up to speed. I got familiar enough with the boost cut that I could even begin to replicate it by giving it a little gas in 8th enough to build up to about 3-4psi, and then I'd watch it cut out completely and go to zero. My assumption for why the issue seemed especially bad this one trip and not other times I'd driven it was potentially just mildly lower fuel quality from a fill-up that exacerbated the issue. Symptoms of diverter valves not holding up would only really be present at full throttle, not partial throttle like you're saying. Your symptoms you're describing are almost textbook symptoms for what I experienced as well as a ton of others in that thread as well. If your car is CPO still, I'd even bet you wouldn't have to pay for the fix to be done either! But even if you do, it's just an hour of mechanic's labor, so for me $180 if I recall correctly. I think I've made that much back just in fuel savings since then!

BrendonSF

I have the issue with boost "bouncing" periodically even after replacing the diverter valves, which I had an indie shop do @wcpfour. The replacement is pretty straight-forward on the V8, a bit more involved on the V6. Still manageable, but after originally having planned on doing it myself, I couldn't figure out how to access them without signficant work.

I've also had the DME update performed as per the bulletin. That mostly solved the issue when I was stock. It's definitely more pronounced with the tune, and now it "bounces," whereas prior to the fix it would just peel it back. Part of me wonders if the engine just doesn't like our lousy California gas.

RhinoComp

I'd bet California gas certainly helps highlight the issue more since at it's core it is an issue of the engine thinking pre-knock symptoms are more present than they really are. Which could also be why someone with access to 93 and 94 octane premium may not notice it ever.

BrendonSF

Yep, we're lower on the octane spectrum that some states. We're also forcused to use a cleaner-burning blend in the summers, and up to 10% ethanol. Our gas is more environment friendly, but less engine/combustion friendly.