hi, im new to the to the turbo world and wondering if someone can help me, so I recently bought a 2010 fg xr6t with 58,000 k's on it, had it serviced about 1500 k's ago and within the first few days after the service noticed a change in power. turbo seems laggy less responsive. the mechanic said all he did was oil (synthetic) and air filter didn't touch anything that would change the power. had computer plugged in to see any registered faults but computer came up normal. have recently noticed a flutter in my exhaust which I'm thinking must be coils or plugs. if it was that wouldn't I notice a rough idol or something like that? always running premium fuel. I know the clutch is on the way out but wouldn't think that's the issue. been told to tighten manifold and change fuel filter and see what happens after that. if anyone has any ideas please share thanks