I have recently changed my sister in laws cylinder head (for a used one) as her cam belt snapped not a good thing on a rover engine especailly a k16 DOHC.I followed the instructions from my haines manual to the letter. 
When I started the car up the engine is now idling at 1500 rpm I have changed the temp sensor and the manifold heater (as it was old and blew the engine fuse). 
Can any one give me a clue where to go next. 
 
Help with  a Rover 424si k16 engine that has had a used cylinder head fitted as the old one the cam
                            
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                        Ignition on, pump the throttle five times, wait 20 secs and start the engine. 
 
It might settle down, otherwise it is a trip to a suitably equipped workshop (Rover dealer?!) for a stepper motor adjust. 
 
Check the simple things like too tight a throttle cable and manifold air leaks firstly...... 
                            
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