MicroSquirt.com read only forum (Jan.15,2018)

Hi all,

Just a note that MegaSquirt should NOT have capacitors installed on the sensor/controller side of the EGO sensing circuit.

On a V3 main board, the resistors R10, R11, and C10 capacitor form the EGO input circuit (R1, R29, and C2 on a V2.2 main board). C10 is on the processor side of the circuit, and is fine. However, some people are apparently adding capacitors to the sensor side of R10/R11. This causes problems with some wide-band controller boards, including the Innovate LC-1. So don't do it.

As well, please be sure to ground your wide band controller to the same point as MegaSquirt, this is an important point if you want you wide-band to read accurately and reliably.

If your MegaSquirt is grounded properly, but the wide band controller is grounded to the cigatette lighter or dash, you might see up to a few volts offset, making the inidcated AFR completely wrong.

Lance.

I am goin to be using MSnS-E with a V3 board and I have a PLX m300 wideband, the manual that came with my wideband says to use supplied capacitors to filter out interferance noise from outside sources like the radio and ignition systems on the analog output wire. What your saying is that I do not need to add this capacitor because MS already has compincated for this or should I install it anyways??

Could someone please reply to above post? I am not very clear on it either, as PLX does say to use a capacitor.

El Nagro,

If the wideband controller manufacturer says to add it, then you can do it.

The concern is not from MegaSquirt's point of view (the capacitor won't damage it at all), instead it is the wideband controller that can be damaged by such a capacitor - and we have been advised by Innovate that such a capacitor should not be used with their products (LM1, LC1, etc.) under any circumstance.

Apparently PLX recommends such a capacitor, so you can install it.

Lance.