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

Hi. I´m going to install the Microsquirt V3 on a SkiDoo 800 ETEC snowmobile. I have a couple of questions :

1. I have a Bosch EGO sensor that is connected to my KOSO instrument, and gets power, ground an signal from the instrument. Can I hook up only on the signal cable, or do I also have to splice the ground and 5VRef on also?

2. Same as no. 1, but for the Bosch 3Bar TMap sensor.

3. Same as no 1 & 2, but for the stock TPS on the snowmobile.

Any feedback is greatly appreciated

Hi Heffa

The KOSO instrument panel has a 5V output if I understand correctly, but the MicroSquirt is only interested in the signal, which it expects to be between 0-5V.
Assuming the KOSO instrument dash is designed for these loads, you shouldn't have any problems, and no you don't want to splice the ground and Vref.

Which model KOSO panel are you using?

Mike

Hi Mike, thanks for your reply.

I´m using this Koso instrument :

http://www.kosonorthamerica.com/koso/sh ... mperature/

My EGO and water temp sensor is powered by this instrument, and if I understand the MS manual correctly, it is only for the sensors that the MS powers that need to be connected with ground and 5VRf also?

Of cours I need to establish som Ohm references on the KOSO water temp sensor to put into the Tuner Studio, but do I really need to feed the water temp into the MS since I´m using it as a fuel only system? The warm up enrichments that the water temp is suppose to support, is taken care of by the stock ECU.

I only use the MS to control the 2 extra injectors that I´m using when under boost (running a turbo setup on this sled).

Hi again Heffa,

If you want the Microsquirt to power standalone sensors using its Vref, then fair enough. I would be little concerned when you say...only using for fuel only and relying on the stock ECU with a turbo set up...because that means your ignition timings might not be appropriate at high boost. I don't do turbos, but I'm sure things burn faster at higher boosts, so you'd need to retard the ignition. So my next question, is can your set up do this?

Mike

Hi again Mike.

At the moment I can not retard ignition timing as you suggest, but I will have this option mid vinter probably. It´s ok to run with the stock ignition as long as the boost levels is kept at a reasonable level.

Thanks again for your replies, they are greatly appreciated.

Havard

Is this EGO sensor wideband or narrow? If it's WB, I would suggest grounding the WB controller, the KOSO, and the uS together, to reduce ground-offset errors.