hi all, i have recently bought a 1.6 a3 from an auction, problem is that its hunting, its ok when first started up but as soon as you rev it it starts hunting between 1000 and 1300 rpm, i looked under the bonnet and found 2 air pipes had been removed, by someone in the auction i expect to try to get it cheaper, i put these back on but its still hunting, could it be a air leak , lamda sensor etc.