Why Does the Dashboard Fuel Consumption Number Jump Around?

[MacJohn]

The dashboard fuel consumption number jumps around due to issues with the onboard computer. Here is some relevant information about the car dashboard: 1. Introduction: The car dashboard is a device that reflects the working conditions of various vehicle systems. Common indicators include the fuel indicator, washer fluid indicator, electronic throttle indicator, front and rear fog light indicators, and warning lights. Different cars have different dashboards. However, conventional dashboards in most cars include the speedometer, tachometer, oil pressure gauge, water temperature gauge, fuel gauge, and charging gauge. 2. Precautions: Normally, the brightness of the dashboard does not require manual adjustment. It automatically adjusts based on the intensity of the external ambient light.

[Leanne]

I also experienced erratic fuel consumption readings on the dashboard when I first got my new car. Turns out it's related to the fuel calculation mode. The instantaneous fuel consumption value updates every 0.5 seconds - it directly shows 30L/100km when you press the accelerator hard, and instantly drops to 2L during braking or downhill driving. Later, I broke the habit of frequent lane changes and tried to maintain a steady speed around 60 km/h on highways, and the fuel consumption display stabilized between 6.8-7.2. If the readings keep fluctuating by more than 2 fuel levels for a long time, remember to check the oxygen sensor. Last time my car had this issue due to carbon buildup on the sensor causing data distortion, and it immediately returned to normal after replacement. Using eco mode during normal driving works particularly well for stabilizing fuel consumption readings, and gentle acceleration makes the numbers less sensitive.

[LeMarley]

Having driven for twenty years, I've seen too many cases of abnormal fuel consumption display. The biggest culprit is driving habits, especially new drivers who tend to brake suddenly and then stomp on the accelerator, leaving the onboard computer no time to refresh the data. Last week, while helping a neighbor diagnose his car, I found that his fuel consumption fluctuated by as much as 5 levels during traffic jams. Later, I suggested using cruise control on the elevated roads, and the numbers immediately stabilized at around 7.3. Temperature also has a significant impact. In winter, the fuel consumption is definitely inflated during the first five minutes of a cold start. It's only accurate to observe after the temperature gauge reaches 90 degrees. It's best to develop the habit of resetting the fuel consumption data after refueling. I do this every time before hitting the highway, as the statistics are then closer to reality. If the car is over five years old, it's most likely due to aging fuel pressure sensors.

[DelGage]

My car's fuel consumption display has been fluctuating between 8.6 and 11.2 recently, and I later discovered it was caused by engine carbon buildup. The mechanic said when fuel injectors get clogged, the ECU repeatedly adjusts fuel supply leading to erratic data readings. Low tire pressure can also cause this - last month my front left tire was 0.3bar underinflated, and the fuel consumption display fluctuated an extra 1.5 points. It's recommended to check tire pressure monthly and use the manufacturer-specified oil viscosity. Short trips are most prone to wild fluctuations, especially frequent start-stops within 3 kilometers when the ECU collects insufficient data samples. I later intentionally took 10-kilometer detours on ring roads, and the fuel consumption numbers stabilized obediently within reasonable ranges.

[DeEmersyn]

I've studied the principle behind erratic fuel consumption readings. The vehicle's onboard computer calculates the value based on wheel speed sensors and fuel injection pulse width. Any signal interference can cause abnormalities. Last time my car's wiring was tampered with at a modification shop, the fuel consumption suddenly started jumping erratically like crazy. If this persists long-term, it could be a faulty crankshaft position sensor - when this fails, even the fuel consumption data becomes inaccurate. A dirty air filter can also affect it, as fluctuating air intake causes ECU misjudgment. I recommend regularly cleaning the air filter - I remove and blow out the dust every 5,000 km. If you see absurd readings like 20L at idle, immediately check the fuel evaporation system for air leaks.