How do you make O2 Sims?

**kool-aide** · 10-26-2009, 05:16 AM

Here is my idea. My car is throwing the P0161 code, downstream O2 sensor heater check thingy.

I really dislike the idea of the downstream sensors. On my 99 z28 one of the downstream O2s would always go nuts in cold weather.

I was thinking of buying an O2 simulator because it is about half the cost of a new sensor,

. Then I had a thought. I have a dead O2 as it is now. I don't have ORY nor will I have the money to get one. Even if I did I would still need to solve the same problem, SES due to O2 sensor downstream.

My plan is to leave the dead one in place, plugs the hole nicely,

. Take one of a couple of options, buy a Sim, buy someone's time to tune it out, buy a new sensor and bust my knuckles changing it.

I like this option. Cut my O2 wire harness right of that dead sucker. Now I have a proper connector and wires. All I am missing is the instructions to turn this nice pig tail of a dead sensor into a Sim.

Does any one out there now how to make an O2 sim, and can it be done by salvaging the wiring off a dead sensor.

thanks

kool-aide

**0verkill** · 10-26-2009, 07:03 AM

the best thing to do is to get it tuned. the sim's only work for a small time if at all.

**kool-aide** · 10-26-2009, 07:15 AM

what is it about making a sim that fails over time?

I was hoping to use/salvage the wiring and connector from my dead O2 to make a sim.

**FORD RECOVERY EXPERT** · 10-26-2009, 07:28 AM

Just need to know what resistance the O2 sensor puts out at optimum performance...

Take a DVOM (Digital Volts Ohm Meter) and read the resistance of a good O2 sensor thats plugged in and working correctly with the engine running. then replace the faulty one (or both rears) with a close value resistor.

**kool-aide** · 10-26-2009, 07:34 AM

Originally Posted by FORD RECOVERY EXPERT

Just need to know what resistance the O2 sensor puts out at optimum performance...

Take a DVOM (Digital Volts Ohm Meter) and read the resistance of a good O2 sensor thats plugged in and working correctly with the engine running. then replace the faulty one (or both rears) with a close value resistor.

please tell me the best place to measure from is not at the plug under the car,

.

**0rion** · 10-26-2009, 09:45 AM

Originally Posted by FORD RECOVERY EXPERT

Just need to know what resistance the O2 sensor puts out at optimum performance...

Take a DVOM (Digital Volts Ohm Meter) and read the resistance of a good O2 sensor thats plugged in and working correctly with the engine running. then replace the faulty one (or both rears) with a close value resistor.

not to say you're definitely wrong but I think there's more to it than that. The reason I say that is the sensor works on voltage and not resistance. The pcm also has to see a certain amount of activity from the sensor or it'll throw a insufficient activity for the O2 so the voltage can't be static. It'd have to fluctuate in a range too because there are high and low voltage codes. There are also heater codes for the rears. Not sure what's involved in building one....I'd love to tear an old sim apart and see what's inside of it but it's more than just a resistor.

**blue02Z** · 10-26-2009, 09:50 AM

orion is right. the pcm sees mV not ohms. i bought my sims from thunder racing back in 06 and they were still working fine as of a month ago when i finally got a tune.

**0rion** · 10-26-2009, 09:51 AM

Originally Posted by blue02Z

orion is right. the pcm sees mV not ohms. i bought my sims from thunder racing back in 06 and they were still working fine as of a month ago when i finally got a tune.

send me one of your sims to tear apart.

**kool-aide** · 10-26-2009, 10:48 AM

thanks guys.

since the rear O2s don't factor into the fuel management or anything else. I will probably sit around debating what I want to do.

When you "tune" them out. Is it just a matter of telling the PCM the car doesn't have them?

I'm pretty sure I can find someone near by that has HP Tuner.

The rear O2 on my 99 always was a real dumb pain. Hated cold weather and hated spirited driving, lol... It was like the O2 for grandma driving, hah.

**blue02Z** · 10-26-2009, 04:24 PM

Originally Posted by 0rion

send me one of your sims to tear apart.

what you send me back??

**justinmc978** · 10-26-2009, 04:47 PM

i'm sure a legitimate hp shop can do this, you might as well get a tune also, i guess handheld tuners can do this??? not sure, but if you have niether go to a shop, they'll tune it better than a handheld will for probably less..