Why has the idle fuel consumption of the car increased to over 50?
2 Answers
Here are the specific reasons: 1. A dirty or faulty engine throttle can lead to increased fuel consumption: The throttle controls the amount of air entering the engine. If the throttle valve plate is dirty, it can cause inaccurate opening of the valve plate, allowing too much air to enter the engine. More air entering the engine means more fuel injection, thus increasing fuel consumption. 2. Faulty or severely worn spark plugs can cause increased fuel consumption: Spark plugs generate an electric spark in the engine combustion chamber to ignite the air-fuel mixture. If the spark plug gap is too large, it can result in insufficient spark, leading to incomplete combustion of the mixture, which increases fuel consumption and reduces power. The same applies if the spark plug fails to ignite. 3. Excessive carbon deposits can cause incomplete combustion of the mixture, leading to increased fuel consumption: Engine carbon deposits are a coking-like substance formed from unsaturated olefins and gums in the fuel under high-temperature conditions during engine operation.
Having run an auto repair shop for over a decade, I frequently encounter cases of sudden idle fuel consumption spikes. An engine shouldn't consume much fuel at idle, so readings like 50L/100km are definitely abnormal. Potential causes include: a faulty oxygen sensor - when broken, it misleads the ECU about air-fuel ratio, wasting gasoline; leaking fuel injectors that directly increase consumption; or a carbon-clogged idle control valve causing unstable RPM and excessive fuel use. Faulty instrument clusters or poor electrical connections reporting false data are also possible culprits. I recommend first checking the air filter - if clogged, restricted airflow increases consumption. But most cases require scanning ECU error codes with a diagnostic tool - professional repair is necessary. Don't delay until minor issues escalate into major overhauls.
