DIY 02 simulator

PittSpeed Automotive
1

heres some stuff to build ur own o2 simulators

the diagram and parts list im posting is for a single output sim
but if u replace the 555 timer chip and use a 556 chip u can run 2 outputs for a car with dual downstream 02 sensors or u can just build 2 single boxes

all in total if u buy all the parts from radioshack the total cost will be 18.53 to build one
if u dont use the leds in the diagram u can save 3 bucks, but it will require adjustment of the one resitor on the output line

ok heres the diagram

this includes the leds but u can eliminate them if u like
http://i76.photobucket.com/albums/j39/lethalrides2k3/diagram-1.png
r1 and r3 = 100k ohm resistors
r2= 1m ohm resistor
r4= 10k ohm resistor

c1 - 4.7 uf capacitor
c2 = 22uf capacitor
d1/d2 are 1.7 volt red leds

now with this setup if u have 4 wire o2 sensors u will need to leave the heater circut hooked up on the o2 sensor or the ecm will throw a heater circut open code

but here is a redrawn diagram that will make it able to replace the o2 sensor completly in a 4 wire o2 application

also this is redrawn without the leds so u will have to use a higher value resistor on r3 to get the output voltage correct
i dont recall the value off the top of my head so i will have to get it for u guys later on
in this drawing r4 will have to be the same value as the resistance measure over the 2 white wires of ur o2 sensor which is the heater circut
so basically u would just ohm out across the 2 white wires on ur 02 sensor and put a resistor with the same value as what u come up with in the r4 spot

http://img145.imageshack.us/img145/9231/o2sim.png

this is what one without the heater circut looks like when done ( one with a heater circut would just have one extra wire comming out of it

http://i76.photobucket.com/albums/j39/lethalrides2k3/o2sim.jpg
o2sim.jpg480×640

enjoy and if u have any ?'s just ask

2

you could also just space out the 02 sensor some which slows down the pulses the 02 sensor sees thus not throwing the code. the spacer trick is less then a few bucks to do

3

yeah this is mostly for cars with ory pipes or that remove the cats/ install test pipes
also cheaper then buying a new downstream o2 sensor if ur car needs one the cheapest downstream 02 for the car i did this for was 68 bucks

4

the spacer does not always work. i know on newer nissans it won’t. nice find/writeup

5

Radio Shack still actually sells electronics parts?

6

I thought they sold GPS & Cell Phones :dunno:

7

not all radio shacks still sell electronic parts, from what iw as told the stores that are in like strip malls will have the stuff, but ones inside like a mall wont sell electronic parts *shrug

8

www.parts-express.com

That’s where I get all my stuff…I didn’t think RS even sold any parts any more.