The digital speedometer can yet posses a mechanical dial readout.
An accurate speedometer can adjust the characteristic between a smooth impel and a ticket. A reading that is off by single a infrequent miles per day in the counterfactual order can easily assign you on the bum side of the rush line. A speedometer is easily affected by kid adjustments to the machine itself. One of the most regular changes that can drastically copper your speedometer's readout is a alter in tire amount.
Instructions
1. Proof your speedometer for exactness. You can asset exactness algorithms available online. These websites Testament challenge you to input incomplex numbers, specifically the bit it took you to hop one mile at a place velocity. For instance, whether you travelled one mile in one minute and registered a precipitation of Fifty mph, then your speedometer is off by Twenty percent. The correct reading should be Sixty mph. This will give you the amount of correction that is needed.
2. Purchase a speedometer adjustment device. This device will plug into your car's OBD2 reader. The device will allow the user to change various settings and readouts within the car. These will run in price from $100 on the low end to well over $1000 on the high end. To make sure that you purchase a quality device, be sure to read reviews and talk to other owners.
Take the car back out onto the road. Go one mile for a full minute at a sustained speed. Run the numbers through the same website you used for your original testing. If the speedometer is correctly adjusted, then you are finished. Select the needed model; the device will have a list of options that can be changed. This includes settings such as odometer and engine codes.
4. Retest the speedometer.3. Follow the instructions provided with the OBD2 speedometer adjustment device. These will vary from device to device. However, in general, there will be a menu that lists car makes and models. If, however, there is still a discrepancy, then repeat the process.
