I used their oil and petrol treatment here on a 16 valve zetec Fiesta once which wasn't too healthy engine wise and it definitely improved things, may have helped clean out injectors or summat. Anyone used it on a scoob? I have vf35 and sti pinks on mapped '03 wrx and it isn't boosting properly ( around .86 bar instead of nearer 1.2 ) Car otherwise runs perfectly OK. Wondered if it may be worth a punt on the off chance it helps to clear blocked oilways. Car is regularly serviced but I'm not currently flush enough for a new turbo which it may need?

 

i would personally check all hoses for splits etc etcr, maybee even clean you boost selonoid first before i would even think about an engine treatment

 

I wouldn't use an additive, all the ones we've had tested are either harmless, but do nothing, the rest can actually cause harm.