wkearney99

Just got back from the dealer. Having the info on the Advanced Bulletin 21704 helped. It was not yet known to the service techs (not just the service manager, but the actual folks doing the work).

They re-flashed mine, but there was no paperwork on it as there wasn't a repeatable problem suitable for a warranty claim. So they did it gratis. I would've preferred to get more info, but I'm not going to complain when it's work done quickly. The actual work took less than a half-hour, most of the time was just waiting for the vehicle to go back to the service bays.

The weather's crappy here today, and it was lunch-hour traffic on the way home thus I wasn't able to discern any difference. Not that it was predictably repeatable anyway. But I'll be on the lookout for changes (good or bad).

Were I not having a consistently repeatable problem I'd probably not get too worked up about having this update done. Like the transfer case, I'm not seeing any signs of trouble so I'm not worrying about it or demanding "something be done". But I'm certainly concerned about it and plan on doing advance preventative fluid changes, most likely when I have the engine oil changed.

I don't have a definitive answer here other than to say the bulletin wasn't yet on the dealer's radar. What that means is anyone's guess. No doubt there's a lot of updates and such across many models. Three other Macan owners where in there for the fuel flange campaign.

When I called Porsche this morning, they called back just before I was leaving for the dealer. It was suggested I mention the 21704 bulletin, which I did. But it was the printing of the rennlist post #104 here that had the right encouragement for them to just re-flash it anyway.

Rads

My dealer here in Maine had never heard of the issue or fix. But I sent him the post originally listed by SCGuy. He checked with Porsche and got back to me, saying that Porsche has acknowledged the problem and come up with a software fix. They installed it two weeks ago, and so far all the challenging uphills on cruise control have worked well. Also, the car seems more "driveable" on the interstates.

So SCGuy, did your fix not hold? Sounds like you still have the basic problem.

SCGuy

Actually, the fix still seems good. Have a drive to the mountains coming up which will be a good test, but so far so good!

wkearney99

I wonder, if the fix surrounds the computer's interpretation of the knock sensor, what 'known factors' beyond the sensor sensitivity would be problematic? Just how sensitive is the combustion cycle to octane variations? I've always put the factory required premium into the tank, but I do tend to refill at the 1/4 tank or lower level, and then not typically at the same stations every time. I suppose it's possible for a station's pump to not be delivering the correct grade. But since we're not talking AV or diesel there's no reliable way to tell what's coming out of the pump.

caronsd

I had the fix applied a couple months ago and all is good so far. I feel like the vehicle is now a little quicker to downshift a gear - from 8th to 7th - when you try to accelerate in a low-RPM/high-load condition (as what was leading to the boost pullback that we have complained about). This would make some sense as part of the fix - I'm not sure if I'm imagining this enhanced downshift behavior or it's real - I'd be curious what others who have had the fix applied feel.....

Rads

Snipe: SCGuy originally posted the fix. Porsche acknowledges the problem, caused by overly sensitive knock sensors. My dealer here in Maine had never heard of the problem, nor the fix. But when I gave him SCGuy's info, he checked with Porsche, confirmed everything, ordered the software update, and put it in about three weeks ago. No malfunctions since. Everyone should thank SCGuy, as I do. The info he gave was:
DME Update as per TI 2470/DME Update ATI 1704.

Give that to your dealer, and things should get better.

wkearney99

I've not noticed anything significantly different. But then the problem was always quite difficult to pin down, for me anyway. Long road trip coming up in a few weeks so I'll be able to give the ACC a better work-out.

Meanwhile I'm still getting the occasional acceleration lag after a turn. It's more repeatable than the lack of boost. Roll up to a stop, turn wheel tight left or right, wait a few seconds and punch it. Starts rolling but without the power I'd expect. Difficult to repeat and doesn't happen every time. I'm going to ask if they've got a GTS as a loaner to see if I can repeat it. The service manager is aware of transfer case issues and was ready get mine fixed should it be a problem. Could just be my imagination and overly spirited driving...

stiles_s

I put a bunch of miles on the car over a long weekend this last weekend. Roughly 500 miles on some great roads, and some of the same roads that reproduced the symptom easily before the reflash.

I'm quite happy to report BOOST. Plentiful, predictable boost.

I'm quite relieved. I'm going to call this one "fixed" in my book. I was pulling my hair out because this is intended to be our family hauler road-trip rig. The flaky boost would have been a deal killer for me.

To reiterate for folks, I had to get mine quite hot. Approx one hour of driving, the hotter the better. Then "lean" on the throttle at freeway speeds to increase speed without a hard downshift. Result: brief small boost spike and then bleeds to zero. In the worst case, it was failing to make boost at just about all speeds/rpms unless I was really caning it.

Snipe656

Mine, 2015 S, was "fixed" in August 2016 via the entire engine being replaced. I guess around a month ago I went ahead and had the software update done after I was informed about it in a PM and of course verified applied to my vehicle.

I definitely had no negative issues introduced from the software update and have used the vehicle to drive to San Antonio(200 miles one-way trip) a few times since the update. The throttle response to me is better after the update, I do think not as touchy, but in a good way because seems like might be the root reason my fuel economy went up some since update.

TxHoon

Well mine was flashed and I managed to make a road trip from Houston to South Louisiana and the problem showed up in Lake Charles (140 miles and 2 hours). My problem is back.

Boost bleeds off when leaning on the throttle, and while accelerating from a stop it is terrible and does not make any boost. It just bogs down and does not want to accelerate.

This would truly be a great road trip vehicle if it worked, but I have honestly lost confidence in it for road trips. Around town it is great including my 90 mile round trip commute to the office, but once on the road, it just falls flat on its face.

I sent an email to the Sales Manager, Service Writer, and the sales guy stating the problem was still there and that it is a safety concern and this was unacceptable for an 1 year old car with 20k miles.

They assured me once I get back to town that they will take the car in, give me something nice to drive and get it fixed or buy it back. 1 month old tomorrow and has been in the shop 3 times and when I return home this will be the 4th time.

It definitely has been a different experience with the 1 month of the GTS vs the 3.5 years of the Diesel.

Really disappointed so far, Porsche should never have let these vehicles leave the factory like this. I know they do extensive testing.

deilenberger

Seems it would qualify for a lemon-law buyback..

Needsdecaf

Not always simple on a used car.

Needsdecaf

That sucks man. Let me know how you make out. They are a big store and they should stand behind their products, especially with a known, common issue like this one.

TxHoon

Ok, just got back from the dealer. The software update they did a few weeks ago did not take. That explains the similar symptoms.

After the update, it runs like a stabbed rat. On the way to the dealer it would not get out of its own way, now I runs better that it ever has. The car was still hot so the 45 min in the service bay would not make a difference. Can't wait to make another road trip with it. Now it drives like it should! Boost here, boost there, Boost Everywhere!

rdboxster

That's great! Hopefully this time things will be much improved. Not sure why a code update doesn't take sometimes. One would think the service rep would verify prior to releasing the vehicle.