Hi scotty i nave a 2005 kia sportage 2.7lt petrol auto.
The rpms are sitting on 1000 rpms on park,Going down to 500 rpms in drive .when I Accelerate it surges until around 50 klms and drives fine until I get to the lights then goes down to 500rpms. It fluctuates between 500-1000 rpms. There is no engine light on .and the diagnosis machine had no codes.
I have replaced air intake valve sensor
Throttle body sensor
Rocket cover gaskets and o rings
Spark plugs and leads
Pcv valve
Battery
Have you checked operation of the IAC valve? Cleaned the MAF sensor and throttle body?
I have replaced IAC Valve replace MAF and cleaned throttle body
I have replaced IAC Valve replace MAF and cleaned throttle body
Did you use factory original parts? Don't use AutoZone branded parts, etc. They're made in China and have lifetime guarantees for a reason -they make them too cheaply. Only use the manufacturer's original equipment for any kind of sensor. MAFs and IACs are precise metering devices.
As a next step, you could measure your fuel pressure.
