Evening hope im in the right place i really need your help i have a 57 plate vec 3 lite v6 cdti thats done just over 12,500 miles i just recently bought a plug and play tuning chip to increase my bhp from 184 to 220 i fitted the chip and the results where amazing however the next day i was driving around (not thrashing it) i pulled over with my engine still running for about 10mins when all of a suden my engine cut out and would not start again i left it for a minute or so then it started again i sat on my drive with my engine ticking over and it did not cut out so i thought it was ok so i had to go to the shops whilst i was stoping starting the ****** thing stoped again so buy this point i took the chip off and put everything back to normal this was last week since that i have noticed my car is sluggish esp when im in 6th gear and put my foot down i used to be away no problem but now i need to change down a gear something i would not have had to do also i dont know if its me worrying but when i use 2nd and 3rd gear i can here a slight vibration sound a kinda knocking sound but when i put my food down it disapears i have not had diesels before so im guesing its becouse im in the wrong gear and its the engine turning to quick i dont know.... anyway there is no blue or black smoke when i start it up my engine sounds fine when im staionary and rev my turbo whistles its just the slugish bit im worried about i know im due a service soon so could it be the plugs need changed or the filters ect some one from thorney motor sport is coming to remap my car but now i dont know what to do please send me a private msg if you have any ideas

many thanks guys