What Causes High Fuel Consumption After Throttle Body Cleaning?
2 Answers
After cleaning the throttle body, fuel consumption may increase significantly in the short term. This is because the original carbon deposits in the throttle body are removed, leading to increased air intake and consequently higher fuel consumption. The situation will stabilize after some time or can be resolved by performing an ECU reset. Below are some relevant explanations: 1. Reasons for increased fuel consumption after throttle body cleaning: The carbon deposits in electronic throttle bodies should be cleaned every 10,000 kilometers or when the fault indicator light comes on. After removing the carbon deposits, the vehicle's performance may be affected. For example, in fuel-injected vehicles, cleaning carbon deposits from the fuel system and throttle body may initially result in higher fuel consumption. The vehicle's ECU requires a learning process to adapt to the engine's new operating conditions after carbon removal, which typically takes about 1,000 kilometers. 2. ECU reset can reduce fuel consumption: Generally, after cleaning the throttle body in a fuel-injected vehicle, an ECU reset operation is necessary. If this step is skipped, it may lead to a significant increase in fuel consumption. The simplest reset method is to disconnect the battery for more than 30 seconds. Reconnect it after a minute, and the vehicle should return to normal operation.
I also experienced increased fuel consumption after cleaning the throttle body, which is quite normal. After removing carbon deposits, the intake system becomes cleaner, but the engine ECU still retains old data and doesn't immediately adjust the fuel injection quantity, leading to temporarily higher fuel consumption. After driving for a week or two or taking a highway trip, the ECU will self-learn and the fuel consumption will return to normal levels. Don't rush to get it repaired unless the high fuel consumption persists or is accompanied by engine shaking, which might indicate cleaning agent residue corroding sensor wires - such as a short circuit in the mass airflow sensor. In such cases, it's recommended to visit a professional shop for an ECU check and reset. Don't worry, regular maintenance can prevent similar issues.
