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

I've tried searching without much luck. My question is has anyone been able to use ms for fuel control only, allowing the stock ecu to record from its sensors? Thanks in advance!

I dont know the details but if you put resistors of the same value as the injectors in place of the injectors the computer will still think that it is controlling everything. also i think all 4 O2 sensors and other sensors need to be in place and hooked up. Talking about faking the OBDII signal to the diagnostic computer that the emissions place uses is strictly off limits on these boards. I am unsure if even this is ok... the admins may delete this post and thats ok but i have seen this posted about before but I don't know if they got deleted. It's somewhat of a touchy subject.

The way that OBDII systems work, terminating the injector connection with resistors would only (possibly) remove the injector warning. The mixtures would all be out of control as far as the analysis system is concerned so things like the cat convertor checks and other checks where the ecu commands altered operating conditions and observes the response would fail. I doubt there would be much that could be done to get around this and retain satisfactory OBDII checks...

Thanks for the reply and info. I didn't know this was such a touchy subject Sorry!

yes, you're up a creek on that one. The amount of effort it would take to fool the computer is beyond worth while. It would be way easier to simply make a circuit to mimick the OBD2 side of the OE computer to say "alls OK!" to the scanner....thats all that really matters as far as that level of emissions testing.

It sucks, our state went to OBD2 code checking/ready test checking also. Older cars are exempt though (pre-95), so the simple answer is, own an older car...but they still have to pass the sniff test, but thats much easier to pass.