What's causing the heavy start on my Renault Megane?

I've just bought a Renault Megane 1.6 petrol. When I start the engine, it starts but loses power at first. It needs a bit of accelerating to keep the engine running. I have changed the spark plugs already, but the problem still persists. Can anyone help with a bit of advice?
Not sure what year but have assumed 2003 onwards. Would suggest that you remove and clean the throttle body (the throttle valve gets stuck because of deposits in the throttle body). This is a known fault on this engine.
Answered by Alan Ross on

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