Its a tdi unless ur a complete banana its hard to fcuck anything up mate,
Warm her up. Turn her off, spray g101 or ag machine cleaner liberaly, leave for 5, pressure wash of just dont hold near electrical areas for too long, restart engine, shut bonnet let it warm up and dry then give a spray with aerospace or ag vinyl rubber, let dry then buff to matt finish.
Job done,
Only clios seem to suffer after a jetwashed bay