when i start the engine it is inconsistent, the revs generated fluctuating between 800 & 2000, & settling between 800 & 1200 with engine running.
My car has 27000 miles.
My car has a manual transmission.
If your engine is going up and down on the RPMs then you may have a leak in the intake air tube from the air cleaner to the throttle body. I would look for leaks in the plastic tubes between the mass airflow sensor and the throttle body. Afterwards, look for any engine vacuum leaks in the rubber hoses connected to the engine.
If you need some help with these checks, contact a certified mechanic, such as one from YourMechanic. They will be able to diagnose your idling issue in person and help you address it from there. Best of luck.
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