SSS2k

Ohh no, not at all. However you will still throw a CEL, and you will pay extra to have an o2 bung welded in, assuming you have a custom one made, so if you dont mind the untidyness, its just as easy to ziptie the o2 sensor to the chassis. Some people have reported no CELs while doing it this way.

Runaround

sss2k - that is pretty interesting about just leaving the 02 sensor out in the open. I suppose the computer be reading fresh air and assume the exhaust has been cleaned enough. i might try that out. thanks guys.

mxt_77

I'd like to hear from someone that has done this. It seems like the ECU would get suspicious when it reads perfectly clean air, but if not, this seems like the optimal solution. Can someone verify?

blues2k3

hmmm...it should throw a CEL due to the temp. If I remember correctly the two white wires are for temp and if there is no temp then there should be a CEL eventually.

chris_barry

The two white wires are the heater coil. Putting the sensor in the air is a novel solution. Be carefull that water and other debris cannot splash onto the sensor or it will be stuffed. Also, due to the heater it can get pretty hot.

Speedracer

Slows2k

It doesn't matter where you put the second 02, If it is not in the Convertor, It will throw a DTC.

If you leave the 02 plugged in, but not in the convertor You won't throw a P0141 for heater failure. You will still throw a P0137, for low output voltage. The computer is watching the secondary 02 to verify the convertor is working, it compares the primary and secondary#'s. The Monitors the PCM runs are 2 trip monitors, So the check engine light may not come on immediately. The car must meet all the operating parameters for the monitor to run, Then run the monitor. It's the second failure of the monitor that trips the check engine light.

red02s2k

hey on my 00 all i did was i went to the junk yard and bought an extra cat and i gutted it out and my car isnt throwing any codes right now and i did this about 2 or 3 months ago

Runaround

Slows2k-
so what your saying is that basically there is nothing you can do huh? Either have a CEL (and possible reduced timing and who knows what else) or leave the cat in. It's funny because I had one of those O2 simlators on my 99 mustang and never had a problem with it. It has the 2 sensor (per side) set up as well.

mxt_77

I know there are O2 simulators for the S2000, too. But I've heard that some of them have problems. You might do a search to find out which ones work right and which ones don't.

Slows2k

For the guys that have no convertor/gutted convertor and not thrown a code, It's only a matter of time. Eventually, your car will meet all the monitors criteria and run them. That's when you'll get the light. The montor's criteria is very specific, the engine has to be at a certain rpm, load, Vehicle speed, for so long before the monitor will run. then a PCM power down, then run the monitor again. This is all governed/set by the OBDII standards. BTW, the DTC for a failed Convertor is a P0420

The O2 simulators work on some early OBDII cars, GM F-bodys, Mustangs, even early OBDII Hondas. Some PCM's are not as"picky" as others.

For example, A 1996 Viper GTS is OBDII compliant for 1996. I know for a fact, the Chrysler PCM doesn't even care if the rear O2's are working. I have 1st hand knowledge of one without any convertors, and has never thrown a light. The Monitors/Tests written in that particular car's PCM are not as specific as Later OBDII PCM's.

The O2 simulators are signal generators. They supply a constantly switching Voltage signal back to the PCM. Some cars are just fine with this, Others want to see the Secondary 02 react to changes made by the PCM to verify they are in fact, working, and the catalyst is operating.