Once again I repeat my suggestion. Do not blindly look for the cause and do not experiment. Find a good diagnostician for engines with PIWIS or go to a dealer. Reading the engine parameters under load can tell a lot about the cause of the problem and the condition of the engine components.
Such diagnostics show how the injectors are working, the condition of the turbochargers, CO2, MAP, temperature sensors, etc., etc.
It's a bit like a blood test of a sick patient.

 

there is a porsche additive see part number on this invoice:

 

I posted a link last month to a YouTube video showing how remarkably smooth and vibration free the 3.0 liter V6 in my 2022 is at idle: https://rennlist.com/forums/cayenne-...l#post19588680

This morning I recorded a short video showing how wonderfully smooth my 2022 3.0 V6 and transmission is after a cold start and as I drive away from my house and out of my neighborhood. It isn't all that far from Lexus LS V8 "smooth" except that I can hear the Cayenne's engine. I couldn't hear the engines in my Lexus LS V8 sedans at all at idle and at similar speeds and had to look at their tachometers to verify that they were running. And my hearing is very good according to a fairly recent test. Here's the video from this morning. You might have to turn up the volume to hear my comments since my FITCAMX dashcam isn't all that sensitive to sound. I max'ed the audio level with Clipchamp but it is still pretty low.




It would seem that those having idling and/or driveability issues with the 3.0 V6 have some sort of mechanical or fuel problem.

 

Thanks to all for the helpful guidance. I’m going to try some injector cleaner and will report back how things go..

 

It’s like teeth whitening strips, need to use a lot of product to get a result. Run through 6 bottles of injector cleaner and report back. 1 bottle will have no effect.

 

Man that's terrible advice.

This is very unlikely to be solved by fuel system cleaner and dumping in 6 cans back to back won't help and isn't recommended by anyone.

The correct answer is noted above...use piwis to review engine parameters when the stumble occurs

 

Here is a link to one of several threads that shows the kind of misfire reports that PIWIS can provide: https://rennlist.com/forums/718-foru...-readings.html
Edit: And this thread: https://rennlist.com/forums/panamera...-misfires.html

I recently watched a YouTube video that showed a bizarre number of misfires - so many that it was amazing that the engine ran at all.

I don't remember any threads about injector failures in the two years I've been on this Cayenne forum. One reason I was leery about buying anything Porsche was due to the high number of injector failures a friend's daughter had on her VW SUV. So many that she dumped the vehicle in frustration shortly after the warranty expired.

 

@LSR has no data from the car.

Chocies are to do nothing or to do something.

Do something options:
- injector cleaner
- throw parts at it
- read codes DIY
- read codes at dealer or cleaner

@LSR what does your gut tell you?

 

Great question! In situations like this, I believe in first trying the approach that is least invasive and least expensive as long as it is not likely to make matters worse. Based on what everyone has written, I’m going to try injector cleaner. My gut says it won’t work, but it might and it’s cheap and easy. If that approach fails, it’s off to the dealer I will go. The dealer I’ll take it to is the one who just solved my 6th gear vibration problem by replacing the transmission mount, after 3 other dealers said “normal.” Another advantage in trying injector cleaner first is I’ll be able to tell the tech that I’ve tried that approach and it didn’t work. That may get the tech to take a harder look.

 

I hope whatever you put in the tank doesn't cause the dealer to say you put in an additive and the manual says not to, and we have no further responsibility. I just don't understand why you are taking the step of putting something in the tank when you don't know if that is the problem? Just go to the dealer first. You paid for a warranty - use it!

 

Fair point. Didn't think of that. I need to make an appointment for new tires anyway, so maybe I'll just raise this issue at the same time.

 

Heeding your warning, I went to my local dealer today and asked my SA what to do if I suspect dirty injectors are causing my car’s hesitations. He said “wait here,” and a few minutes later returned with a can of 44K Fuel System Cleaner. He said that’s what the shop uses in the cars. Good enough of an endorsement for me! When it’s time for a fill up, I’m going to try it.

 

Porsche DOES recommend fuel additives. It might get a tad expensive to use themwith every tankful, though.

https://www.porsche.com/china/en/acc.../fueladditive/

Also, Porsche would love it if every hiccup your car has makes you take it to the dealer. That’s their money-maker, the service and parts dept.

FYI clogged fuel injectors are not a warranty item. Don’t confuse a warranty with service wear and tear.

 

IMO, the above is the key piece of information.

Everything is fine after your engine has been warmed up. Everything is far from OK when the engine is cold. The same engine in my 2022 runs perfectly when "cold" (75 degrees Fahrenheit) with no hesitations or stumbles at all.

Something is defective that starts working better after the engine is warmed up. The challenge is finding what that something is. If I had to guess, it would be something electrical since metal expands as it warms. My guess is that it is something ignition related such as a coil or even a lose connection.

My suggestion is to have a tech do his diagnosis when the engine is cold even if it means leaving your Cayenne at the dealership the day before the diagnostic activity.

Using the fuel additive you were provided isn't going to hurt anything but it doesn't seem appropriate for this problem. Do you buy fuel from questionable sources? It's pretty unusually to get tainted fuel these days - at least in First World countries.

 

You hit the nail on the head. That’s why my gut tells me the additive approach won’t work. But a fuel system cleaner is an inexpensive and easy first thing to try. We shall see.