After replacing a faulty ignition coil on one of the spark plugs (got error message with a diagnostic scan tool) and also replaced all the intake manifold gaskets (one gasket was leaking, mechanics tested it by spraying carburator cleaner to show me which one was leaking), the engine was running smoothly again (had bad misfires before repairs). But now I am getting a high idling. Engine idles at between 1200 to 1500 rpm. Any ideas why this can be happening or how I can get the idling back to normal again will be appreciated. I have a 2011 2.0 petrol Powershift RHD model with 199000 km and is in South Africa.