Sorry....no Veg oil in a 2.2DTi, only decent diesel!
Yes they do suffer some niggling faults, but all are well documented on this site......and I have suffered from most of them
Dashboard - intermittently working - sometimes helped by turning side lights on!
EML coming on - vacuum pipes perishing when 4 -5 years old
Power performance with EML on under load - MAF sensor
Bad starting (regardless of temp) - leak off pipes split. (or very rarely exhaust valve seat damage/dirt)
EGR valve sticking due to dirt/carbon build up
Heated mirror switch - under rated for continuous use - remember to turn them off after 5 mins
airbag light on - bad connection under drivers seat
high temps when towing - ignore it

unless well into the red
slow warm up from cold - replace thermostat
4x4 light flashes - vacuum pipes perished PS Don't use 4x4 on normal roads, only on wet fields and mud, (or snow)
Engine/gearbox mounts go soft if used for towing
regards
Gav