Tiptronic Cayenne stalled in reverse, should I be worried?
 

This morning my 09 cayenne gts stalled in reverse as I was backing out of my driveway. The car started up normally and didn't give me any other problems through out the day but I have never had this happen to me before. The car is still under warranty so if it happens again I will bring it in but is this something I should be concerned about in the future?

Hi Matt - I would definitely bring the car to the dealer asap; especially since it's still under warranty. Any issues with the transmission should be addressed right away. Just my 2 cents...

Thanks for your input, reason I hold off on bringing it in is because the dealership won't touch anything unless they experience the problem first hand. It's a bit difficult for me to say this is a an on going problem when it has only happend once. For my sake any idea what could have caused the car to stall? I was thinking something fuel pump or idle related.

I would start by checking for water intrusion under the front carpet footwell areas. Not under the floor mats but under the actual carpet. You will need to pull up the carpeting. See if your wiring harness is wet, there is a harness on both driver/passenger sides

Were you backing up or down an slope, or just flat?

If you have an OBD2 adapter you could check to see if it's thrown any diag codes. Not sure how many (if any) would show with a generic adapter, but ones with Porsche-specific features would likely show any detected error codes.

Car was backing down as my driveway is on a bit of an incline, nothing major though. I won't be able to read the codes but wouldn't the check engine be on if there were any?

As others have suggested, check UNDER the carpet for ANY signs of moisture. There's a lot of wiring under there and if there's any leaks into the passenger compartment they'll wreak havoc on the electrical system.

As for code, actually no, not all codes will trigger a check engine light or message on the MFT. No idea why, but some don't rise to the level of a CEL warning, apparently.

No water under the carpets, why does seem like the cayenne's all have drain issues? Not to long ago I had a pool of water in the back where the spare is and the rear drain hoses had to be replaced. While the dealer was fixing that they also informed me that the whole head liner of the car was soaked and had to be replaced! Everything was covered under warranty thankfully but wow very surprising.

If there's a sun/pano-roof then, like any brand vehicle similarly equipped, they have drain tubes that WILL get clogged. They have to be periodically checked otherwise the water WILL find somewhere more expensive to drain. Then there's air conditioning and cowl fresh air systems, which also run risks of getting clogged.

Otherwise unless there's a windshield trim leak, or bad door/liftgate weatherstripping there's not much else that would lead to water problems.