About 6 months into my 2007 V8 Vantage (6 speed manual) ownership.
Purchased with 20k miles, has run great after some basic maintenance. Put around 3k miles since ownership.

On a recent road trip I noticed it acting very sluggish after 20-30 miles. First thought was bad cats. Then my emissions light came on followed by check engine light. Next morning when I brought to shop all warning lights were off. Problem seemed to be progressively worsened. No codes on computed, none even stored.
They diagnosed a bad throttle pedal. New part came in and did not solve the problem.
Have a great local exotics repair shop but they are baffled.

Before I ship to AM dealer (3 hours away) anyone have any experience or thoughts?

Starts up fine, revs fine and sounds solid. Feels very sluggish in 1st & 2nd but gets a little better in 3rd and up. No signs of bad clutch either and no warning light.

 

Can you define a little bit more on "sluggish" ?