Well the pedal is defo stiff so its effected by something. Hmm, what to do?!
Maybe a second opinion at another garage is the key.
Can I eliminate the throttle body by disconnecting the cable and seeing if the pedal is still stiff, or some other bright idea.....
Ger
Get another garage to look at it. £500 to recondition the throttle body sounds like a lot. You pick one up from a scrappy cheaper.