Where are BB O2 Sims? (HELP)

Originally Posted by SoloII///M

You should probably do some searching here on what causes a CEL when you install catless headers - this all has been covered over and over.

Obviously your post-cat O2 sensors will throw a code without cats because your catalytic converter efficiency has failed. If you install O2 simulators in place of your O2 sensors (which still won't let you pass emissions in most states) you'll get a code for O2 sensor heater circuit failures because the sims don't have a heater circuit built in.

You can use the post-cat O2 sensors for this. They have heaters in them. You can plug them in just for purposes of having the heaters in the circuit. You can hang them in the drug bin or just screw them into the headers. Doesn't matter where you put them, they just need to be in the circuit.

But thats not going to remove the check engine light. Ur saying to just plug them into the bungs or hang them from the drug bin but that doesnt solve anything. Here in idaho we dont have the sniffer test, all they do is check and make sure you dont have a check engine light via obd port.

Originally Posted by dinan19

But thats not going to remove the check engine light. Ur saying to just plug them into the bungs or hang them from the drug bin but that doesnt solve anything. Here in idaho we dont have the sniffer test, all they do is check and make sure you dont have a check engine light via obd port.

I'm not sure how to explain this such that you'll understand. I really think you need to do a search.

Your O2 sims in the O2 sensor line circuit (theoretically) will prevent the CEL from the car thinking the post-cat O2 sensor is reading rich from having no cats.

Having your O2 sensors plugged in the O2 heater line circuit will prevent the CEL from the car thinking the O2 heater circuit is missing. Get it?

Originally Posted by SoloII///M

I'm not sure how to explain this such that you'll understand. I really think you need to do a search.

Your O2 sims in the O2 sensor line circuit (theoretically) will prevent the CEL from the car thinking the post-cat O2 sensor is reading rich from having no cats.

Having your O2 sensors plugged in the O2 heater line circuit will prevent the CEL from the car thinking the O2 heater circuit is missing. Get it?

I think so. I appologize as im very non knowledgeable when it comes to wiring and electrical. Do you mean that the post o2 sensors would need to be wired into the heater circuit. Correct me if im still wrong. Lol

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Most people just install high-wattage resistors and hang them in the drug bin. It's much easier to just hang the O2 sensors in there (since you're not using them anyway) and wire them in just like the factory did.

Originally Posted by SoloII///M

Most people just install high-wattage resistors and hang them in the drug bin. It's much easier to just hang the O2 sensors in there (since you're not using them anyway) and wire them in just like the factory did.

ok so cut off the end of post o2 sensors and wire the high wattage resistors to the ends of the sensor wires. Is that correct?

Originally Posted by dinan19

ok so cut off the end of post o2 sensors and wire the high wattage resistors to the ends of the sensor wires. Is that correct?

No, that's not correct.

Cut the signal wires and install your O2 sims. Then, using the uncut wires that go to the stock O2 sensor connectors, plug in your stock O2 sensors. Done.

But again - in most states the O2 sims will NOT allow you to pass emissions.

Originally Posted by SoloII///M

No, that's not correct.

Cut the signal wires and install your O2 sims. Then, using the uncut wires that go to the stock O2 sensor connectors, plug in your stock O2 sensors. Done.

But again - in most states the O2 sims will NOT allow you to pass emissions.

This is confusing the crap out of me. But im sure ive prolly already given you a headache and i appreciate your help even though im still confused. Ill just keep searching and try to get some more information.

Originally Posted by dinan19

This is confusing the crap out of me. But im sure ive prolly already given you a headache and i appreciate your help even though im still confused. Ill just keep searching and try to get some more information.

I'll try to make this as simple as possible.

Each O2 sensor has four wires. Two are for the heater. These are usually white. One is a ground. This is usually gray. One is for the lambda measurement. This is usually black.

Your post-cat O2 simulator creates a signal on the black wire that fools the computer into thinking there is a post-cat O2 sensor present and working correctly. You can put this O2 simulator wherever you want - it doesn't go in the exhaust. For the two heater wires, you're going to leave these connected to the car's post-cat O2 sensors. You can either hang the O2s in the drug bin or just screw them into your headers. It doesn't matter. They're not doing anything but completing the heater circuit so your car doesn't throw a code.