Snipe656

I just got mine back two days ago and seems fixed, I plan to take it on a road trip in two weeks to be certain.

They replaced the entire engine.

Good luck, I fought for months over this and a real challenge was even finding a dealership that believed me.

SCGuy

I have the same issue. Took it to the dealer, where it is supposedly a known problem...they have other Cayennes with the same issue. They captured some "raw data" and sent it to Germany...I will be following up with them on next steps.

WhipE350

Wow, what a read. I wonder why I continue to love this brand. I can't believe they are still in the deny first and blame customer mode for issues like this. Here we are 16 years after the first IMS bearing issues and it seems nothing has changed. I'm going to the dealer tomorrow with a buddy to service his 911. We'll be test driving more cars again, that is how we like to spend the time waiting. We usually buy a new Porsche every year or two from them. I would love to get the sales side of things take on this thread.
I'm sure I'll hear all car companies behave this way and just have to live with it, but boy it sure does give one a bad taste.
Good luck guys.

Snipe656

Definitely a bad taste for me but this was my re-entry into the brand after probably 15ish years and back then was a used Porsche I bought from a family member. I don't see me getting another one. But hopefully the current one will at least last for a little while so can actually enjoy it over wanting to blow the thing up daily because became so painfully sluggish to drive as the time went on with the problem getting worse in that time.

Oddly enough I know from personal experience not all companies behave this way. Unfortunately I know for Ford and Honda, neither of which really make a single thing that interests me one bit.

caronsd

Any updates or additional occurrences of this problem? Took our 2016 GTS up into the Sierras last weekend and was surprised at the lack of power on the climbs (I have several other turbo vehicles, so have a good idea of what to expect). On the way home, was using the cruise control and found the same issue as others reported - could not hold a speed of 75 on a slight climb. I kept my eye on the boost gauge - in the higher (cruising) gears, at the initial increase in throttle position, the boost would quickly build to 0.3 Bar (say 1-2 seconds) and just as quickly drop to 0 and stay at 0. I would increase throttle with no increase in acceleration until the transmission would downshift 1 or 2 gears. All this time, the boost remained at 0 Bar.

Anyone have anything additional to report from dealership visits with similar problems/symptoms? Thanks for any/all replies!

Snipe656

Exact symptoms mine had. The vehicle is going into a poor fuel quality mode is why the boost acts that way. If you were to floor it you will see decent amount of boost because it can't back it all out in that scenario. If history repeats itself the dealer will tell you a software fix is in the works but look at the dates of posts on this thread to show how long that story has been out.

Your best bet is to video the car not making any boost when it should then showing that to the dealer.

Good luck. My replacement engine now has 4-5k miles on it and not had this issue.

moosehead

Subscribed. Crap.

whitecayenneS

Interesting. Seems as if you're getting close to understanding the issue. Poor Fuel Quality. Perhaps a bad sensor, or bad system that measure fuel quality? The "we're working on a software fix" is a good sign. I've found that German companies absolutely refuse to ever, under any circumstances admit fault. Press them and they'll walk away, even while they know deep inside that it's their fault and it's their task to fix the problem. They won't admit fault.

I have a BMW motorcycle and it's the same way with the Mothership. Forget trying to force them to admit there's a problem. Rest assured they're working on it, and they'll probably find the problem and implement the solution. But they won't admit it. Ever.

They'll quietly issue a software fix and combine it into an update of some kind. Everyone with the problem will notice it's been fixed, but not a word from the Company. And the Service Managers either really don't know or are told to keep quiet.

I hope they fix it soon for you guys. What is it with these proud German companies? Maybe I just answered my own question - pride.

Snipe656

It is not actually bad fuel quality or even detonation about to occur that is causing the vehicle to go into poor fuel quality mode. Nor is it as simple as just a bad sensor. Once my vehicle had been into three dealers and on it's 4th or 5th visit it got escalated to the regional technical manager. He diagnosed the issue with the dealerships lead technician and explained to me what is happening to cause that mode to engage and approved what he felt was the best fix for my problem.

Maybe one day they can come up with a software fix, but just look at this very thread and you will see people have been getting told for around a year that a software fix is in the works. That does not instill confidence in the story of a fix in the works if you are driving a vehicle that when the issue is happening you can't even speed up or maintain speed well enough to pass a loaded down Uhaul truck who instead passes you(I am not exaggerating here).

It is a very frustrating problem because there were times I drove very long distances before getting to dealerships to ensure it would happen when I took a mechanic with me but vehicle would act up none. The real key to getting them to believe me was providing multiple videos showing without a doubt the vehicle would not make boost as well as some videos showing how it runs when making boost. Annoying problem with getting it diagnosed is they need it to happen for them while they have a computer(laptop) hooked up so can read things since nothing about this issue is stored in the computer as some sort of fault/problem.

deilenberger

Care to share what he diagnosed and told you? And what the fix was. Was it a replacement engine?

Snipe656

I already stated the fix, perhaps indirectly, but yes it was complete engine replacement. They felt that by the time these issues are escalated to that level it would be better to replace the entire engine over having a dealership tear into someone's engine to try and figure out what is creating a poor fuel quality scenario when one truly does not actually exist. That way the engines with the problem get sent back to be diagnosed and a fix hopefully developed.

I rather not misquote the guy since it was an entirely verbal conversation and nothing in writing about the diagnosis process. But that was the basic gist of what I left everything with back in August last year. At the time he went into more details about knock sensors, processes the vehicle takes, and so on to how they used all things while actively driving it to figure out and confirm the issue.

Another thing that I just remembered was that it helped me out that I log all my fillups and keep the receipts with mileage written down on them. They even said in person how having those receipts and seeing not only octane put in but fuel brand and different locations was helpful. It was hinted that perhaps I was just putting wrong fuel in it or always going to the same exact station and it had bad fuel tanks. They did still take a sample from the tank and tested it somehow just to make sure.

cdog533

Guys, I have a 2016 GTS... I typically use manual mode for the Tiptronic, so I see the lack of boost situation in higher gears fairly often.

On the highway, at say 75-85 mph, if you go full throttle (but stopping prior to triggering the gear kickdown) in 7th or 8th gear, the boost will flash up to 4-5 lbs. for one second, then rapidly fall back to zero and stay there. As a general rule, if you are lugging the hell out of it in the higher gears, it will accelerate very, very slowly, with no boost - even under full throttle conditions.

If you go down to 6th gear, you will get some boost, but you don't see 10+ lbs until you get around 4,000 rpms.

Why does it do this? I figured Porsche wanted to keep boost off the engine in situations that are prone to induce detonation (i.e. pinging). So, instead of possibly running into detonation while under boost, it cuts boost until it's sure no detonation will occur (at higher rpms).

Now, if you kick it down to 3rd or 4th or something, it will make close to 20 lbs. of boost from 4,000 rpms or so all the way to redline.

EDIT: ***THIS IS NO LONGER ACCURATE - SEE MY POST BELOW***

EDIT: *** ACTUALLY THIS IS ACCURATE UNDER SOME SET OF UNKNOWN CONDITIONS... SEE MY VIDEOS LATER IN THE THREAD ***

Snipe656

i don't ever use the triptronic so can't speak directly to how things act in a properly running vehicle v. one that has this issue. I can say though when this issue is happening the vehicle will maybe hit 0.1-0.3 BAR of boost but quickly zeros out and makes none after that. The vehicle will be so low on power that it can't maintain speed with light throttle(no more than cruise control applies) if encountering any sort of inclines. If the vehicle is working correctly though it takes very little throttle in 8th to see 0.1-0.2 BAR and the car holds the boost with that throttle level, it does not zero it out.

Here is a video taken south of Austin on a very small hill. I sped the vehicle up to 84 just before I started the video at the bottom of the hill. Cruise is trying to hold speed and you will notice boost is zero and vehicle even downshifts trying to make it keep the cruise setting and end of video vehicle has hit some level ground. Cruise control just makes it easier to show the problem, I have videos I took leaving stop lights on level ground with 1/4 throttle that also show lack of boost across multiple gear changes.


https://youtu.be/hZSN6WS35f0

Snipe656

I just tried this a few times and mine does not accelerate by much but it quickly hits 0.5 BAR and keeps the boost there. To try this I got up to 75 mph then would either move the shift over(or paddle down one then up one) and downshift then upshift so in 8th and in manual mode then roll throttle down to just before the downshift spot.

moosehead

^Trying to interpret the above Triptronic manual shifting outcomes vs. auto, are you guys saying you need to downshift to coax boost and that only happens in manual paddle shifting modes? For further carification, are the above shifting experiences in negatively impacted GTS engines or properly functioning powerplants?


Not looking to create a food fight, really want to understand this. While this may be an obvious statement, IMO, todays trannys are more than capable performers in auto so the above Triptronic discussion leads me to believe that this is the potentially serious matter that the OT is based upon?


FWIW, I have yet to take my bride's new GTS out for a proper romping but this thread gives me the excuse to do so against her better wishes.


Thanks for the clarifications.