Ihave a 96 XJ6 VP. Wife was driving home yesterday cruising at 70 mph and she said it felt like the car shifted down to a lower gear. Engine was losing power and would not get above 20 mph. She shifted lanes to get out of the way of other cars and then it regained power and was OK rest of way home? I have also noticed a few hesitations in power at mid range speeds. All fluids are at proper level. Tune up performed recently. Also, it has a VERY high idle in the mornings and takes a awhile before it goes done with a sticking feel on the acc pedal. Once it goes down the pedal doesnt stick anymore. I manually reved motor up at throttle body area and can feel it stick. After the motor idels down there is a clicking noise at the black vaccum box in front of throttle cable thatit hooked too. I was thinking fuel fliter, pump, sensors? Any suggestions would be a appreciated.

Kgg