UK Car Repair: question, air leaks, manifold inlet

Question
William hello,
I have just bought a Renault master van 04 plate the throttle is fly by wire. When pulling away and you change gear the revs take ages to drop hence it makes driving a bit difficult please can you advise where the problem is.

Thanks
Bob

Answer
First check there are no air leaks into the manifold, inlet hose broken, clamps loose, etc. Next clean out the throttle body, often, goo gathers and prevents the throttle plate from closing. Unplug and plug the electrical connectors to the throttle body, there may be a bad connection. Apart from these checks there is little you can do other than change the throttle body, before doing so take the vehicle to someone who can read the on-board computer to confirm.