Mate I had that issue with mine after I thought all my dramas had been solved.

It ended up being a rubber t-piece that had split. 2 second job to replace.

If Lane tuned it it won't have anything to do with the tune, it will be something mechanical.

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[COLOR="Red"]I have the right foot of Subaru death![/COLOR]

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365hp and 515nm

New Beast to arrive April 2015 - 365hp, 450nm, 0-100 in 4.4sec. AMG Goodness!