I am looking to make my own O2 bypass using the vfaq link provided below:

http://www.vfaq.com/mods/O2bypass.html


Today I picked up the following from Radioshack, although before I cut the O2 sensor I want to be sure that this stuff is the right stuff for my application. Someone who is more savvy at electronics please tell me if this stuff will work!

 

I guess I'm the only one with a check engine light because of my test pipe?

 

anyone? bump

 

Actually most people either use a mechanical fix or buy an electronic emulator..

The problem with what you want to try is you need to simulate an ouput signal thats similar, but different to the front o2 sensor..

I don't know of anyone who has made their own simulator and gotten it to work.

 

Thanks for answering my PM! Well I guess what I am looking for is if these will work according to the Vfaq. I want to make sure they will be heavy duty enough.

 

Maybe I should explain why this won't work a little better..

the ECU is smart enough to expect to see a signal with voltage that fluctuates from .5v to .9 volts, and if it sits at any particular output voltage for any period of time, it triggers a check engine light...

the correctly way is to simulate a voltage that sweeps back and forth at fairly random intervals, but generally "leaner" than the stock front o2 sensor..

From the looks of the circuit, the resistor is the load of the sensor, and the capacitor should simulate the charge/discharge (voltage sweep) however it probably will not work because it doesn't simulate the function of what an O2 sensor would appear to look like to the ECU.

If you want to "Test" to see if it works, I wouldn't remove the O2 sensor, leave the heater circuit wired up to the stock sensor, and connect the capacitor and resistor portion to the wiring harness ahead of the stock O2 sensor.. Unfortunately odds are this won't work since the output of that circuit won't fluctuate enough to satisfy the ECU..

This typically worked with older ECU's which only cared that the sensor was there and working, but didn't read the sensor too closely.

 

Bump, any ideas on this?

 

ok well i just got on .. and saw your post and request... that method wont work on the evo. i have try it... not all cars are the same. that method will work on subarus but not on the evo . dont know why./..
i made a o2 sim that works awesome on the evo i sold plenty of them but i have none made at the moment. shoot me a pm and ill make you one.. i actually have 2 more guys that are in need on some o2 sim i can try to built some this upcoming week.

 

Just live with the check engine light or splurge for the perin test pipe and sim good deal to get them both in a combo.

 

I want to put a wideband where the current O2 sensor is. I want to remove the sensor completley.

 

Why don't you put in another 02 bung? It's not time consuming and any exhaust shop can do it.

 

agreed +1

 

well witht he sim i make you can take the sensor out not disconected but take it out of the bung. it will have to remaind plug to the car but out of the bung...