urgent help needed
fiesta rs turbo

car has some kind of problem and im at my mums with it atm,

its as if there is an air leak, poor idle, if idles at all, boost gauge was orignally at -20 now sits around -10-14 up n down now and then, runs poor unless on hard boost but backfires etc etc if u rev it

any1 have any ideas how to cure it?

 

As you say sounds like air leak, or running very lean for some reason.
Just make sure everything is tight.
tabetha

 

everything is tight, when im driving the car and take my foot off the gas the boost gauge goes to -20 as it should but if i stop or dip the clutch it goes to -10 and sounds rough