I'm gradually sorting out my 98 XK8 Convertible and I feel that I'm almost there. Today I took my car for its longest drive since buying it. Over 3 hours.
I've been getting a random Restricted performance message which doesn't always appear and if it does, always disappears once the car is turned off. The most noticeable difference is that it is always accompanied by a red light and never a check engine light. Equally mysterious is that there is no loss in actual performance.

My investigations in JTIS show that there is only one DTC that relates to this combination of RP and a red light, and it confirms that there is no limp mode initiated. The DTC is P1250, which is for the Throttle body valve spring. I haven't found any definitive information anywhere on this DTC and consequently no solution.

As I don't really have any driving issues, I'm not losing sleep on this one but it would be good to clear this one up if I can.

Any ideas out there?

Thanks in anticipation!

Phil