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I have some issue that i wonder what is the problem, i have the error code P222728 ( ambient pressure sensor) but do not affect driving and performance so i do not care about it. there is some other issues, as same as pumping petrol a lifetime, which is i think i need to change the petrol tank floater or something about that,
but recently i found out every morning, when i start the car normally it will auto warm up maybe for 10-15 min, before the RPM goes down. but recently it do not happened, but when i off it and restart it will warm up. any ideas anyone?
 

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The ambient pressure sensor is important as it measures same and thereby is an input to the Engine Control Unit leading to the proper air-fuel ratio for optimal performance.

If your fuel gauge is you believe showing an inaccurate reading of the fuel in the tank than yes it could be a faulty in-tank float sensor. It's a fairly simple device with a float affecting the electrical resistance output to the gauge.

Vehicles are rolling computers these days and will often "cold reboot" after an extended shutdown and reset items. If your 'high idle kick down' returned to normal the next day this is likely the reason. If it doesn't return to normal then you do have an issue where again the ECU is likely getting a faulty input and thereby keeping the idle at high RPM's.
It could also be as simple as a faulty coolant thermostat not allowing proper flow once the engine is warmed up and thereby a sensor providing a confusing input - "it should now be warm but it's not so maintain high idle." Thermostats are a high wear item being continuously immersed in water, the universal solvent.
 
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