Australian Car Repair Issues? Ask an Auto Mechanic for Answers ASAP
Hello and welcome to just answer. I value your input so I can help you better. is the engine light on or can you pull up any codes? if it does it when warmed up it could be a coil, spark plug or even a vacuum leak .You can easily check for vacuum leaks around the intake and throttle body with spraying throttle body cleaner around those areas and see if the rpms go up.
Thanx for that info, You can check for electrical brake down around wires and coils by removing any covers over the spark plugs wait till night ,run the engine and mist water over the wires and coils. If they are bad you will see sparks in the bad areas. But see if somone can check the ECU for any codes would help .