I'm planning on adding a 1Mohm resistor and a 4.7uF capacitor like the picture below on a o2 sensor that generates a voltage from 0 to 0.9v. The plan is to remove highly frequent voltage changes and allow the lower slow voltage changes to happen. Basically frequently changing voltage reports ineffecient catalytic converter so with the resistor and the capacitor apparently this allows the slower less frequent changes but smoothens out the faster frequent changes. This diagram is a tried and tested one based on youtube and the person who did it has had it over a year. My only question is, is there a need to put maybe a diode across from the + and - just like the capacitor?