i have a uk turbo on a p plate its got a full ss exhaust uprated headers k&n filter and a turbosmart megasonic bov i am only getting 16 mpg is this right or is there sumthing wrong this is under normal driving not with a lead right foot

 

Leaking BOV or faulty lambda?

 

did u remap it when you uprated ur headers?

 

how could i tell if the lambda is dodgy, it is an adjustable you can turn it to hard or soft its on soft