Why does my mpg fluctuate so much?

Why does my mpg fluctuate so much?

A bad fuel injector or dirty/old fuel filter can drastically affect the flow of fuel into the engine. A fuel system problem is one of the most common causes of poor gas mileage. The more you run your A/C, the lower gas mileage you will get.

How does the MPG gauge work?

Instant mpg displays give drivers the exact miles per gallon they’re getting at that very moment. The devices have sensors that take into account the car’s engine speed (how hard the engine is working), the fuel-flow rate, manifold pressure and throttle position.

How is instantaneous mpg calculated?

The ECU has calculated how long to open each injector for each cycle. By adding up all the open time in a short time and multiplying by the known flow rate the volume of fuel used is known. Divide the distance traveled in a set time by the fuel used in the same time and multiply by a constant will give the mpg.

What is distance to empty?

Distance to empty calculates the approximate distance you can drive with the amount of fuel remaining in the tank. This calculation is based off of the average fuel consumption over the past 20 miles of driving along with the amount of fuel left in the tank.

Why does my car gauge fluctuate so much?

Your car is pre obd2 which means there probably is no way to reliably look up what the computer is reading and what it is putting out to the gauge. It could be a loose wire. best way to isolate this is drive over a sharp small speed bump or 2×4 quickly and see if it reliably causes your gauge to fluctuate.

Why is it when driving the RPM gauge drops or jumps up?

Somewhere the fuel drop then suddenly rpm decrease better check the complete fuel system from tank to injectors also check the rpm sensor . Was this answer helpful? This could possibly be your output speed sensor, related to the transmission.

How does the instant MPG readout work in a car?

While many cars have fuel economy gauges that display the average fuel economy over time, instant mpg readout lets drivers see exactly how much gas stomping on the accelerator pedal actually burns. Instant mpg readouts and other instant fuel economy displays have been a part of the green driving movement for some time.

What do you mean by temperature gauge is fluctuating?

Temperature gauge is fluctuating, sometimes showing overh… Q: Temperature gauge is fluctuating, sometimes showing overheating.