I have owned a 2009 XF V8 Supercharged for about nine months. It is fairly low mileage at 55,000. It usually starus right up and runs very well. However occasionally after running the car and then shutting it off it refuses to start. When I press the start button I get a warning (transmission fault) when I attempt to start again the warning sometimes that changes to (cats fault). After the car sits for a little while it starts right up and runs perfectly. The failure to start time period varies from 3 minutes to as much as 45 minutes, I have taken it to my local foreign car specialist Dream Cars, Victorville, CA which has all up to date Jaguar diagnostic soft6ware but they can not diagnose the problem, as they have never experienced the problem while the car was in their shop.

Does any one recognise this problem?

 

When it won't start are the brake lights coming on?
When it won't start try pushing harder on the brake pedal to see if that helps?
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not sure about the brake lights. I will check that when the problem occurs next time. I have pushed very hard on the brake pedal with no result. Thank you for the advise.

 

That may not be the problem but it has been reported a few times. Can't explain it but different cars require different amounts of brake pedal pressure before they will start?
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