Practical Standalone Tuning: Reluctor Sensor
Reluctor Sensor
01.50
00:00 | -A reluctor pick-up produces a sinusoidal waveform, which means the direction of current flow and the polarity of the voltage output is constantly changing. |
00:09 | The amplitude of the waveform also changes with engine speed. |
00:13 | This means the peak voltage produced increases with the engine RPM. |
00:17 | If your ECU has an option for tuning a pull-up on or off on the trigger input, this should be set to off with a reluctor sensor. |
00:24 | There are a couple of important points here, first we need to be certain that the polarity of the sensor wiring is correct. |
00:31 | A reluctor sensor has two terminals and it will produce a signal regardless which way the sensors wired. |
00:38 | In it's correct polarity the waveform will look like this, If the sensor's wired backwards, the signal will look like this, the waveform is basically inverted. |
00:50 | If the sensor is wired back to front, the engine will still run but it will result in the timing drifting as engine RPM increases. |
00:58 | At best this will result in wildly inaccurate timing and poor running. |
01:03 | In worst case scenarios it could cause engine damage so we need to be sure it's correct. |
01:09 | The best way to confirm the polarity is correct is to connect an oscilloscope to the sensor and look at the wave form the ECU is receiving. |
01:17 | This makes it very clear if the sensor's wired correctly, and you can check the waveform while cranking the engine, you don't actually need it running. |
01:26 | Most people don't have an oscilloscope though, so another option I use is to check for timing drift once the engine is running, we'll look at this in detail in the base ignition timing module. |
01:38 | As well as the polarity we also need to be concerned about the arming threshold and the filtering we deal with each of these parameters seperately in this module. |