GTV 3 Litre - 'Flat' spot in acceleration
I'm driving a 3 year old GTV, with the 3.0V6 engine. Having some problems with its acceleration at the moment - wonder if anyone can help:
I put my foot down and off it goes, nice and quick. Then (esp. in 3rd gear), when it hits about 3,000rpm, the acceleration stops and it feels like there's a rope pulling it back. If I keep trying to speed up, it eventually gets through the flat patch and carries on going - but it's a bit rubbish if trying to overtake someone (or just burn away from some lights).
Potentially relevant - I had an Autodelta ECU tune up a few months ago + they fitted straight through exhaust (which sounds fantastic). Also, the throttle potentiometer went wrong the other week - Autodelta fixed that (for a small fortune) but it's still got this flat spot in accelerating.
Any ideas what this could be?