Why does the idle speed stay at 2000 RPM and won't drop?
2 Answers
Reasons and solutions for the idle speed staying at 2000 RPM are as follows: Reasons for high idle speed: The carburetor throttle return spring is too soft; Carburetor gasket leakage; Excessive idle jet size; Loose throttle shaft; Poor operation of individual cylinders; Intake manifold leakage due to improper fixation; Brake vacuum booster air valve leakage or other vacuum pipe leakage; Distributor contact gap too small; Or possibly excessive carbon buildup. Solutions: Turn on the air conditioning and rotate the steering wheel while idling. If the idle speed doesn't increase further, it indicates the idle switch isn't closing, which can be resolved by adjusting or replacing the throttle position sensor; If high idle is caused by intake pipe leakage, it can be fixed by sealing or replacing related components; Clean and inspect each fuel injector's spray quantity and check for blockages or leaks; If excessive carbon buildup causes high idle speed, promptly clean the throttle body and idle air control valve to resolve the issue.
Once my car's idle speed kept staying above 2000 RPM, causing fuel consumption to skyrocket and worrying me about engine overheating. It could be that the throttle body accumulated too much oil sludge, jamming the air intake, or the air filter was clogged affecting airflow. It might also be a faulty idle control valve unable to adjust, or malfunctioning sensors like the oxygen sensor sending wrong signals to the ECU. Start with simple fixes: remove and clean the air filter, clean the throttle body and fuel system, and see if the RPM drops. If not, check if the spark plugs are worn out causing poor ignition, or if there's a vacuum leak making the air-fuel mixture too rich. Prolonging this issue may harm engine efficiency. I recommend visiting a repair shop to read trouble codes with a diagnostic tool and fix it early for peace of mind and safety. Avoid DIY tinkering to prevent further problems.
