Pretty simple issue to explain but what is going on?

If I floor it (WOT) the car will kick down and fly! But when you let off throttle response is severely delayed until you restart the car again. It is not sporadic. It happens every single time you WOT. Then restart the car and all is well again. Good news is I very rarely find a need to floor the pedal due to the fact the car gets up and goes briskly with just moderate throttle .

Any ideas here? Thx

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