Can i build o2 sensor simulator without leds (1.7v@20mA)

If I can, then how:
1. what components needs instead leds;
2. have any schematic?

 

Hi guys.

I have one question.

Can i build O2 sensor without led (1.7v@20mA) bulps.
If i can, than how.
Which component needs instead leds.

 

Here is my design. The newest design is the smallest one. Just a note, I deleted one led and replaced it with a 10k ohm resistor. It will reach 1 volt when the input is 16 volts. At 14.6 it's at .8 volts.
Is it better to make it turn on and off every second or keep it how it is?

 

Also is it supposed to stay on for the whole 3 seconds then turn off for the whole 3 seconds? That's what all three of them do

 

What would happen of you run the Simulator on the pre-cats if your running a Piggyback computer? I'm thinking nothing because ur not using the stock O2's anyway. I would assume that this Simulator Simulates voltage, if so would you happen to know how much voltage equals air/fuel ratio of 13 or even 14?

 

Think about what you are saying. If you replace the pre-cat sensors with a simulator, how is your ECU going to know the A/F ratio? If the ECU doesn't knkw the A/F ratio, how can it control your engine? A simulator on the pre-cats will almost certainly cause your ECU to go full lean or full rich. Best case, your car wouldn't start. Worst case, your engine would blow. I cannot speak for what would happen in your case. Furthermore I would not recommend anyone try this hack anymore.

And to answer your other question, no, this simulator does not simulate voltage. It simulates duty cycle and pulse frequency.

 

Interesting write-up. I've had my share of CES lights because my cats or downstream O2 sensors going bad. Might have to give this a try. Thanks

 

Am I understand everything clear: I need to find two wires (74 and 75), cut them and side which came to my ecu connect with circus output, leaving another side of this wire, yes?
If this is clear, then can i connect this emulator straight to o2 sensors (connect to this two wires just in another place)? Because i dont want to damage wires straight near ecu, i think its easier, if something gone wrong, just change o2 sensors, not wires through all car

 

 

Hey guys I wanted to chime in and say I was getting the typical codes after installing catless pipes. I built this circuit and it got rid of the codes but in my case I also had the p1283 code and this resolved that as well. since that code wasn’t listed in the original post I thought I would share my results, I have an 05 base and now at a little over 700 miles after install and everything is running fine with no codes