What is a speed sensor? Pretty much all BMWs use a speed sensor to monitor rpm, ABS and traction control/ASC operation, windshield wiper speed, cruise control and of course the speedometer. In fact, the speed sensor is one of the most vital sensors on the car. The sensor is plugged into the back to the differential and takes its reading from the trigger wheel inside the differential. Like an oxygen sensor, the speed sensor is multi-functional and does a lot more than just send a signal to the speedometer. The DME relies on the speed sensor signal to set the maximum rpm in each gear.

What problems come up with the speed sensor?

1. Whether you are building a racecar or performing a engine conversion this software can save you from re-wiring the car as you will no longer need to send a speed signal to the ECU (Engine Control Unit).
2. If you are an endurance racer this software is a must! As you probably already know, the differential generates a lot of heat and will often melt the speed sensor mounted in the cover. With the sensor destroyed, the ECU would limit engine speed to 6000 rpm! And since most sanctioning bodies don’t allow the use of differential oil coolers this has been something you had to put up with. But now you can race on without the ECU cutting your rpm short.
3. If you are removing the instrument cluster to install an aftermarket cluster or a data-acquisition system you will need to remove the ECU’s requirement for a speed sensor signal.
4. By removing the ECU’s speed signal requirement you can delete some wiring inside a racecar and save some weight – and saving weight equals lower lap times!
5. If your car has an engine conversion done (E30 with US S52 3.2 engine, for instance) then most likely you have run into speed sensor problems. Having done enough of these engine conversions and built many racecars and running into the same problems, we’ve come up with a solution that doesn’t involve the time-consuming task of re-wiring the car.

What does our speed sensor delete software do? These special programs do not need the signal from the speed sensor so that part of the software is erased. Instead the DME relies on the specific parameters and data points within the software itself. We don’t delete the sensor itself since other parts of the car rely on its information. Instead we remove the programming from the chip so the DME doesn’t look for the signal anymore.

This is not a catch-all answer to every problem that crops up with racecars or during a engine conversion. But like the other parts we have developed, it makes the job, and life a lot easier.