Hello, so I have a 2002 Jaguar X type 2.5 manual. I just got a few days ago and the guy said it needed an o2 sensor. When the engine warms up, when you press the throttle down, the car starts sputtering and jumping a little bit. It doesn't do it when the cruise is on or if I'm just keeping my speed steady, and it seems to do it worse in the higher gears. I'm completely new to owning a Jaguar. So if someone could point me in the right direction, that would be extremely helpful.

Thanks!

 

It could be that and/or more, here is a general description of the problems they can have:

Troubleshooting Oxygen Sensors « Walker Products