Why does the old Changan Mazda 3 consume more fuel and what are the solutions?
3 Answers
The old Changan Mazda 3 consumes more fuel mainly due to excessive engine carbon deposits. Here are the measures to solve the high fuel consumption: 1. Clean the engine carbon deposits. Excessive carbon deposits in the engine are a very important reason, mainly caused by the use of inappropriate fuel. It is recommended to add a certain amount of cleaning agent when refueling, and after cleaning, it is best to drive the car at high speed for a while, which helps to increase the exhaust volume and allow the stronger airflow to carry out larger carbon deposit particles. 2. Check the oxygen sensor. As an internal control unit of the car, the oxygen sensor mainly monitors the fuel-air ratio of the engine. Once it is damaged, it will cause an imbalance in the fuel-air ratio of the engine, and the fuel consumption will definitely increase suddenly. After the oxygen sensor is damaged, the exhaust pipe will emit darker exhaust gas during driving, and the oxygen sensor should be replaced at this time. 3. Regularly replace the three filters. During the use of the vehicle, the oil filter, air filter, and fuel filter must be replaced regularly. If they are not replaced for a long time, they will become dirty and affect the use, and transmit wrong information to the engine control unit, causing incomplete fuel combustion and increasing engine carbon deposits.
After driving for so many years, I've noticed that high fuel consumption in older Mazda3 models is quite common. The engine gets worn out, carbon buildup affects fuel injection accuracy, and with aging ignition coils, the spark plugs burn slower, leading to incomplete fuel combustion. Low tire pressure also increases resistance, naturally driving up fuel consumption. As for solutions, I usually check the air filter myself and replace it promptly when it's dirty—it's cheap and easy. Regularly cleaning the throttle body and fuel injectors can be done DIY with online tutorials. When driving, avoid sudden acceleration and maintain a steady speed on highways. Get an annual service, including an oil change. Following these steps, I've managed to reduce fuel consumption significantly and extend the car's lifespan. Older cars need careful attention—saving fuel and money while prioritizing safety.
From a maintenance perspective, the main reasons for high fuel consumption in that car are carbon buildup clogging the fuel system, aging oxygen sensors providing inaccurate fuel measurements, or ignition module failures causing misfires. The solution requires a professional approach: find a reliable repair shop to thoroughly clean the fuel lines, replace the sensors and spark plugs. During maintenance, don't overlook the transmission fluid and tire checks—overly soft tires increase rolling resistance and fuel consumption. It's recommended to inspect every 5,000 kilometers and address issues promptly. Older vehicles also need engine parameter adjustments to optimize combustion efficiency. Practice safe driving by accelerating gently, avoiding overloading, and not overusing the air conditioning. These measures can reduce fuel consumption, extend vehicle lifespan, and prevent roadside emergencies.
