VE 2007 HSV R8 reduced power mode code P2135
P2135 Throttle/pedal position sensor/swithch voltage correlation.
Always did it when I was overtaking, I lost power very disconcerting and dangerous.
Pulled out the Acc pedal, clean contacts and thought I had fixed it as it went away for a month or so.
But came back, lucky I have andriod ph, with blue tooth connection to OBD port, so could clear fault on the move and get my power back for the rest of the trip.
But to dangerous and was scared to put foot down, not much fun when driving a V8, So I got a price for Throttle body from local holden dealer $2000 OMG.
So straight on Ebay and got one a week later for $300 from USA.
Fitted in 20min and that has fixed it. Yay no more reduced power or fault codes.