Porsche cayenne 2009 sat nav. display used to show hours/mins to destination and miles. By itself it now shows km and eta. I want it to show miles and eta

Under the front passanger's seat.

needs satellite update software https://www.ebay.co.uk/b/Vehicle-GPS-Software-for-Mercedes-Benz-E-Class/139837/bn_16385438 neeeds updating new updates have new sat config for satalites upto 20 more

This could actually be a fault in the quite a few different modules.
It could be the centre console buttons, or even the main module.
Unfortunately you need to get VAG-COM or VCDS to see the error codes.
I used a Ross-Tech cable and determined the issue was a failed module.
Any VW, Audi or Porsche service place can connect in and see what the car is reporting.

But this may be best to let Porsche run diagnostics.
Also if it is a module, dealerships tend to have to replace them.
As second hand modules have a CP protection lock on them.

I am not a Cayenne guy but first and formost the timing belt on Porsche's absolutely must be changed every 60k miles or sooner and the water pump every other time, just for good measure. A rough idle after 1 hour driving does not sound like a timing belt issue to me. I would call/attend a local Porsche Club of America (PCA) event and ask around as to who the best mechanic/shop owner is. In the mean time, IF it is the timing belt DON'T DRIVE IT!!!!! if the belt breaks while the engine is running, you may as well buy a new engine! Get very familiar with everything Porsche and your vehicle will last and love you for a very long time. If you don't it will destroy you and your pocket book!

I hope this gets you in the right direction!

Mike Schindler
85/2-944NA
88-944 Turbo
76- 911S Race Car

Mercedes commans sat nav version 4.1 for E220, is saying off road, and when at home is showing on map that I am somewhere in the National Park Peak District. I have been told to remove fuse for sat nav should be no 28 but in boot of car near sat nav cassette fuses in box only go upto 20. Am I looking in the right place?

Press and hold the Menu button until "Adjust Clock" comes up on the display
- Use the "arrow" buttons directly below the Menu button to set the hour
- Press Menu again and use the arrow keys to set minutes
- Press Menu again and choose between 12 and 24 hour clock
- Don't do anything else for a few seconds and the clock mode will turn off automatically

I have 2010 Porsche Cayenne and Nav screen just goes black and turns back on - sometimes it does it few times a day sometimes its working fine ..any idea?

If you don't have a Porsche dealer near you, check eBay for a Nav manual. Your car should have come with one though. Good luck!

it sounds that you need to calibrate it , get your hands on the car manual and see if it has the procedure to re calibrate it