I have a 2.8 diesel 2007 grand voyager.

Im having issues.

The car stops, no spluttering, just cuts out at about 2500 revs if you accelarate too hard, and also now having issues with gear changes from what i think it 3rd to 4th at about 45 mph at just under 3000 revs, it tries to change and cuts out instead.

any thoughts??? I have had a new throttle pedal.