...Some dealers are mod friendly and many are not. But they just can't say your car is modded so it is not warranted. The mod has to be a possible cause of the issue... If you have a Cobb tune and a suspension issue they are not related. Even if they may be, some dealers will work with you to help get it covered.
I'm going to chime in here on this because your assessment is an often encountered misunderstanding of the realities a person might face when something expensive gives up the ghost after modding. This is going to be long but I think it's important for folks contemplating these kinds of mods to go in eyes open. Keep in mind here Gents that I am not an attorney, what I am going to pass on is some information about what you will face that I learned years ago while pursing an M&M action to its conclusion.
The first thing to understand is that possession is 90% of the law. When a car is purchased it comes with a warranty but you do not possess it, this because in order to utilize it you must go to a third party who also does not possess it. The third party is your dealership and it is Porsche that in reality possesses your new car warranty. The dealership is authorized by Porsche to act on a number of issues without first seeking approval from Porsche but for others they must first get approval from a regional rep before they can perform the warranty work. The line between what the dealership can do and cant do is primarily defined by cost. A power mirror goes out and the dealer can order parts and install them without approval from Porsche, lunch an engine and they can't. In the latter case that regional rep has to come in and approve the warranty coverage.
Who is this rep? He/she does not work for the dealership and does not sell cars. He/she does work for Porsche and has a specific job, to guard the gate. They can't be negotiated with and you will seldom have the opportunity to try, they don't have any mercy because they are not there to care for customers. They are highly trained and in recent years have gained significant tools to help them find abuses or ascertain the existence of other conditions that might have led to a failure.
Now we can talk about what happens when the rubber meets the road, we'll use a blown engine for our example. There you are, enjoying the new found power from anything; headers, tune, blower, doesn't matter. Suddenly you come to a stop with a lot of sickening noises coming from the engine. The car is towed to the dealership where they determine the engine is toast. Your dealer can't repair this without getting approval from the aforementioned rep. He comes in, does some investigating, determines that the car was modified so as to increase the power. He/she will then tell the dealership that Porsche will not be authorizing the warranty coverage. The reason will be because the car was modified to have more power changing it into something that they did not and do not sell. They have no obligation to warranty something they did not sell. I was told behind closed doors depending on the circumstances and the cost the dealership will often argue in favor of the customer and sometimes succeed but more often not. However that may be the dealership must now choose to either pay for all the parts themselves and cover the labor gratis or inform you of the bad news. Most of us are not going to be good enough customers to get the dealer to good will an engine meaning you're about to get a call from a service adviser that isn't good news.
So there you are... You decide to ask for a manager, service, sales, whatever. You make your case but get nowhere. You try to reach out to ownership, you get nowhere. You decide maybe it would be better if you drive down to the dealership and talk to them in person. You jump up and down, yell, scream, site the M&M act. It means nothing. You are not in possession of your warranty and never have been, in order to deny it the dealership needed only to say the words and it was done. But wait you say, Porsche cant do that, the M&M act has language stating that the dealer has to prove that the parts caused or contributed to the failure. You're right but not being in possession of the warranty you have to go through what may be a long process to prove it and it wont be cheap. Someone might tell you that the M&M act provides for the ability to ask for fees and it does but you are not guaranteed to get them even if you win. I won and asked for fees but did not get them.
Remember the part where it's said they have to prove the cause? Again the reality is quite different than you might imagine. What happens is they have a "stock" case for most potential denials which includes expert testimony and a whole bunch of charts and graphs. They take this and adapt it to your particular case and should you go to court will present it as their argument. There is no beyond a shadow of a doubt because this is not a criminal case. That information will be taken as truth and you lose automatically unless you produce all the information needed to refute it. You are in other words going to be in the position of proving you are innocent.
That folks is the reality of what you might face. Might. A lot of things can happen on the way and if you're honestly in the right you should see the coverage you were denied and have a good shot at getting fees as well. You should not however take that as a certain outcome.
I've avoided talking about specifics because individual states have their own laws which can further impact warranty litigation but I have a few other observations. The first one is that people often talk about having their warranty voided in total but this is only possible under specific circumstances that wont typically apply to the discussion here. That I can remember off hand are odo tampering and salvage title but there are a few others. What you are going to be faced with is a denial of a specific coverage and/or the further the possibility of having the drivetrain warranty voided for power adders. The remainder of the warranty will remain in effect regardless. Also about these reps I think it should be understood that they aren't evil and are not necessarily out to get you. I once chatted briefly with one of these fellows when getting oil changed on one of my Corvettes. There was a slight leak at an o-ring from a fitting under the oil pan and they brought me back to show me. As I was standing there looking another fellow came over from a different car and looked at it. He asked about the car, how I liked it, the usual chit-chat from what I assumed was another car guy and he moved on. I had noticed the dealership guys were a little nervous during the conversation and it turned out that would be because the fellow I had been chatting with was one of those reps and the conversation had occurred just a few feet from my shiny new long tube headers. He didn't say a word about them although he had clearly seen them and nothing ever happened with my warranty. No flags, nothing. Would things have gone differently if he saw those headers and the car had just came in with a blown engine? Probably.
I'm not preaching at anyone here, I'm a modder and have enjoyed the hobby all my life. Enough so that while I have no intentions of modding the Macan I couldn't resist coming to this section and reading about it anyways. I posted because I hate to see this kind of information go without some clarification about the real world of the process because the possibility for harm exists. I've no idea what an engine, tranny, diff, etc, cost here but I would be willing to bet many people would find replacing some of these items painful or might not be able to pay for them at all in a pinch.
Please keep in mind I'm not trying to scare anyone. It isn't likely most people will have a problem, it's a matter of what happens if you're the one that got unlucky. For myself I've gone both ways even after my encounter with Chrysler and the M&M act. Back when I had an E92 I decided I didn't want to be on the hook for a 26k engine and left it alone, I could have swallowed that pill but there would have been tears staining the check. On my Vettes on the other hand I let fly. In no way do I know what is right for anyone else other than to say that IMO a gut check should be made before proceeding.