Some owners said that after car maintenance, fuel consumption did not reduce, but increased than usual. It can be said that the performance of the vehicle will be improved after maintenance, especially after replacing the spark plug, the engine combustion performance will be better, fuel consumption should also be reduced, so the fuel consumption did not reduce but increased why?

Oil and spark plug problem

If the oil used is different from the previous oil, the old oil is not clean, and the oil is added too much, which will lead to the oil viscosity is different, and increase the working load of the engine. To gain more power, fuel consumption must increase.

Not only that, more oil will not only increase fuel consumption, and the engine will become "dead", if added too much oil, it will increase the burden of scraping down the piston ring oil ring, dirty oil will flow to the upper stream, when the carbon is burned in the combustion chamber, the oil will pollute the three-way catalytic converter, even exhaust gas will emit blue smoke.

Fill to the correct oil level and keep the oil level at the center line of the oil gauge. In addition, do not assume that the higher the oil viscosity, the better the lubrication of the engine, too high viscosity will also lead to increased engine running resistance, so before changing the oil, please confirm the recommended oil user manual model.

Spark plugs need to be tightened according to torque, but many maintenance masters basically rely on the feel of touch, that is, basically feel appropriate, and then the strength of the maintenance personnel if not skilled, often too much force and make the spark plug on the ceramic part of the crack.

In addition to choosing the matching model, you should also tighten the spark plug according to the standard torque specified by the manufacturer, otherwise there will be gas leakage, high temperature and high pressure gas will slowly leak out, leading to the engine becoming weak and idling, unstable, high speed is easy to stall, fuel consumption increases, and even the engine can not start, resulting in serious consequences, such as spark plug failure and engine damage.

Cleaning throttle after not reconfigured and three way blocked

Because the opening of the throttle will increase after cleaning, the engine computer will still use the opening parameters before cleaning to control the intake and fuel injection if there is no need to check the computer for rematching and resetting, thus increasing fuel consumption. If the throttle cleaning project is completed during maintenance, it is possible that the throttle cleaning failed to match, return and rematch. Fuel consumption will be normal. It is usually recommended that throttle 20,000 to 40,000 be cleaned once, after cleaning, you must use the computer for pairing and learning.

If carbon deposits are removed, travel and operation will be normal, because the travel computer needs a certain number of miles to adapt to the clean working conditions. However, the three-way blockage caused by the removal of carbon deposits will also lead to increased fuel consumption if carbon deposits are removed.

Reset average fuel consumption and replace brake pads

The average fuel consumption is reset during maintenance, so the fuel consumption is recalculated, and if it is not driven at high speed immediately, the recalculated fuel consumption will be falsely high and drop after a few hundred kilometers.

After replacing the new brake pad, the friction gap is relatively small, relatively speaking, the resistance formed during braking will lead to a slight increase in fuel consumption, the brake pad run-in period is very short, usually about 300 kilometers. But that would only result in a small increase in fuel consumption, not a big one. During maintenance, maintenance and inspection are not standardized, and after maintenance is completed, the various conditions mentioned above that lead to increased fuel consumption do indeed occur. When the car is being serviced, it is essential to go to a professional repair shop. Do not increase the consumption of the car to save money.