On my 2006 jag s type I'm randomly getting a "restricted performance" message, then engine loses power and ability to accelerate; stays like that awhile, then just goes back to normal performance.
That message seems to pop up when the car is cold or hot, it could be related to a vac leak(s), dried hose(s), bad gasket(s) you may want to have the car scanned to see if any codes show up...
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