Seems like it would be possible to make your own O2 sims with some resistors or something. Has anybody done this that would like to share their experiance?

 

I thought about possibly useing an A-stable 555 timer circiut to simulate O2 switching but dropped the idea since I have edit. Has anyone ever looked at the output of an O2 simm w/ an O scope?

 

Yep, you are going to have to use a 555 circuit or something like that to give it a "swinging" signal. If it's not switching fast enough, etc. it will set a code also.

http://www.mkiv.com/techarticles/oxy...sor_simulator/

Might be a good circuit/starting point.

 

Excellent! Thanks, guys! I've put together many 555 timer circuits in the past, so I should be able to whip this one right out. I'll report my results back here when I'm done tweaking it.

Maybe I'm just a cheap bastard, but I can't see paying $90 for a pair of these units when I have piles of circuit components laying around waiting to be used. I won't have to buy anything if that ciruit will work.

 

let me know when you get it done, I need some.

 

Ive got a couple of homemade ones on my dining room table, along with a huge sack of GM connectors. I'll be selling them a lot cheaper than $90 a pair once I get finished testing them.

And yes, I used a 555 chip.

 

Mine toggle between 435mV and 735mV. I think the mimimum switch time is 3 cycles per second.

 

Cool. Let us know how It works on your car, I'd like to know just for the fact of knowing. I am thinking a 555 circuit that produces an ajustable PWM(pulse width modulation)signal would be the easier to get working with the PCM due to the fact that you can you can readly ajust the switching fequency and average mV to keep the PCM happy.I'm going to try it and see what happens.

 

Thanks for the voltage and frequency specs, guys. I'm going to be wiring up a 555 ASAP!

 

any updates did you make them yet or no

 

you can disable them with tuning software easily today, compared to the post 6 years ago, also the EPA does not tollerate manufactures of "defeat devices" which the O2 simulator is guilty of, One could manufacture these easily, and sell them, but it would be foolish, especially with case law against you, using the caspers vs epa case.

http://www.epa.gov/compliance/resour...sper-fcsht.pdf

Ryan

 

There is still a company making these, they call them Signal Conditioners. PM me if you want, you can also drill out a spark plug non-fouler with a 1/2" drill bit and plug that in the pipe between the bung and the 02, it pulls the o2 sensor out of the exhaust stream.

 

I wonder whether just hooking B2S2 input to B1S1,
and B1S2 input to B2S1, might give you a sufficiently
different signal to fool the catalyst efficiency tests.
With only the cost of some wire & soldering.