I have a high idle rpm

Yes it is high if it still does that when it is warm. Cold idle speed is higher. Perhaps they will slow it down at first service.

Typically, the idle speed will be set at a value in the range of 600 to 800 RPM, but the exact value will depend on the number of engine cylinders and whether the vehicle is equipped with a manual or automatic transmission.

Kia Sportage Engine idle speed is high Inspection Costs

Thread: 6.0 V12 XJS High RPM When Warm - Jaguar Forum.co.uk

www.jaguarforum.com/showthread.php?t=54266
Mar 3, 2013 - I recently bought a 1993 6.0 V12 XJS and when it is started from cold it runs ... to 1300 RPM so it wants to surge forward when braking which is strange. ...Classics · XJS 3.6,4.0,5.3 & 6.0; 6.0 V12 XJS High RPM When Warm ... You might want to adjust the aux (extra) air valve to bring the idle speed down.

Cars are design to run at a higher idle at start up to warm them up quick. There is a sensor that reads water temperature and tells your car's computer how fast to idle. Your RPMs seem slightly high but not out of the norm. Does idle ever drop to around 600/800 after about a minute? If not, your engine temperature sensor maybe defective.

This is normally the way it is suppose to work. You need to have the RPM measured for High RPM and duration. What you are describing is how an electronic choke is suppose to work.

The errors would be how high the RPM goes and for how long it lasts. When cold the RPM, fuel mix and timing are changed to give a rich fuel mix. As the O2 sensors warm(Could be defective) they signal the engine to lean up. The water thermostat also has something to do changing the engine to a lean running slow condition.

If obtaining heat from your heater seems to take Forever, the thermostat could be weak. This would coincide with the engine continuing at a high RPM longer because it is not warming up.

Check the water coolant thermostat. If it is stuck in the "open" position you are heating up all the water in the coolant system and this will take time. The thermostat keeps the water in the engine until warmed up to almost normal running temperature, only then does it allow the coolant to enter the radiator.

white smoke out of the exhaust would be a sign that it is burning coolant... if it goes away after it warms up, it could just be condensation inside the exhaust pipe. 1800 rpm is a very high idle, maybe have your IAC motor on the throttle body checked... check engine light? if so have the code read at your local auto zone.

check out the idle control valve first

it seems that the auto choke setting is maybe wrong or there is a problem with engine management, or a worn part which is sticking.

when cold, the engine should be higher as the choke will be on but a warm up idle of 1200 seem a bit high i would expect around 800 and then on restart if the engine is warm then the choke should be off but the idle being too low indicates one of the above.

check all your vacuum hoses and the throttle body itself for a vacuum leaks if the hoses replace as nessasary if to check for throttle body get can of carb cleaner and spray around base of throttle body and sides not in it if idle raises you have a vacuum leak goto a good parts store and ask for a rebuild kit don't goto auto zone or advance they don't carry them

when cold it will idle a tad higher 850 - 900 is normal cold , and around 600 warm. if it is idleing high after warm up then check for excessive coke<carbon> build up in intake and throttle valve.