my rs turbo is running 2 stage switchable boost done by last owner, engine runs starts fine with no smoke but when turbo spoules up the car takes off but then most of power is lost. turbo hold perfect boost. at around 16psi i think it could be a fueling problem or timing. has anyone on there had this problem or can point me in the direction of what to cheek

thanks for your help

mike

 

you could check CO on idle, if the metering unit is working correctly it shouldnt be a fueling problem.

check the ign timing make sure thats right , anything between 9-12 should be fine for a starting point.

also check all round for airleaks as there are loads of places for these old cars to piss air out

failing all that, take it to a specialist who will have the correct equipment/knowledge to make it run sweet again