This could be bad ignition switch, grounding on starter or to the block, or aggressive detailer! My Cayenne had terrible demons after I had it detailed. I had instructed them not to lift the hood to clean the engine (my thoughts on ALL cars). Water pressure can get to electrical places under the hood that are water tight but not for high pressure. They called me 30 minutes after I dropped it off and said it wouldn't start. I went right back there and saw that they had used a 3000 PSI pressure washer to clean the engine compartment (#@$#$#$##!!). Water in electrical can cause shorts and and multiple connection points that should be isolated from one another. I left it in their heated space with the engine hood up and windows open until the end of the day and it started. I had seat buttons that would push the seat forward when I asked it to go back, a window that wouldn't open, radio turned on/off randomly, and sometimes the car would not start - lights came on inside but starter would not turn on! Through the summer the problem got better and eventually the car was fine. Permanent damage can happen with pressure washers so I like a dirty engine after detailing. If you want a clean engine allow them to wipe the top and sides but no pressure washing under the hood!
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This could be bad ignition switch, grounding on starter or to the block, or aggressive detailer! My Cayenne had terrible demons after I had it detailed. I had instructed them not to lift the hood to clean the engine (my thoughts on ALL cars). Water pressure can get to electrical places under the hood that are water tight but not for high pressure. They called me 30 minutes after I dropped it off and said it wouldn't start. I went right back there and saw that they had used a 3000 PSI pressure washer to clean the engine compartment (#@$#$#$##!!). Water in electrical can cause shorts and and multiple connection points that should be isolated from one another. I left it in their heated space with the engine hood up and windows open until the end of the day and it started. I had seat buttons that would push the seat forward when I asked it to go back, a window that wouldn't open, radio turned on/off randomly, and sometimes the car would not start - lights came on inside but starter would not turn on! Through the summer the problem got better and eventually the car was fine. Permanent damage can happen with pressure washers so I like a dirty engine after detailing. If you want a clean engine allow them to wipe the top and sides but no pressure washing under the hood!