Who makes MIL eliminators for the 2010 camaro??

[Clear Image Auto (Dan)]

Take a close look at the cat converters and the O2 sensors. No secret, just some creative fabrication. Thanks Mav.

[MadMav]

I'm guessing that the angles provide some sort of benefit? I'm at a loss.

Mav

[Clear Image Auto (Dan)]

Originally Posted by MadMav

I'm guessing that the angles provide some sort of benefit? I'm at a loss.

Mav

Yes, with the sensors removed from the direct exhaust flow, the PCM receives the correct info when comparing the before cat to after cat readings.

[MadMav]

Figured, but couldn't put it into proper words. Thanks,

Mav

[GNVenom]

Time to put in a bit of tech stuff.

If there were no cat, the front sensor data would EQUAL the rear sensor data in O2 content. The PCM looks at that, and determines the cat is not functioning. Sets the code. Now, if a cat is functioning properly, the rear O2 will see LESS oxygen, since the cat is consuming oxygen to finish the combustion job. Also, the "activity" of a lambda sensor is very fast, and reacts quickly to the amount of oxygen in the stream.

An oxygen sensor works this way: The oxygen in the exhaust stream is compared to atmospheric oxygen. This means the O2 sensor needs a "reference" source of oxygen. It gets this from one of the wires that run from the connector to the sensor (the wire acts as a conduit to bring outside air, including oxygen molecules, into the reference electrode). AND, this is the reason you DO NOT CUT O2 SENSOR WIRES and try to splice or solder them - you'll cut off its oxygen supply. The sensor then compares the inside oxygen content to the outside (atmosphere) oxygen content. The lambda sensor is actually a device that produces electricity, in very small amounts. If there is more oxygen inside of the exhaust stream (lean condition), the sensor produces little voltage. If there is less oxygen inside (rich condition), the sensor produces more voltage. And if the oxygen inside is equal to outside, the sensor produces a default voltage (It's just under half a volt, 450 millivolts to be exact). This is known as the crossover point, the infamous 14.7:1 air/fuel ratio (you may have heard the term "cross-counts", this the point at which the voltage crosses over).

But I digress...the post-catalytic converter sensor must operate more slowly than the pre-cat sensor. And it must see less oxygen. If it does, the PCM is happy and all is well. And obviously, it must track the difference continuously to maintain peak cat performance. It's about the air we breathe, right?

Off the soapbox for now.

[g-townmach]

If the rear sensor is seeing equal or more oxygen like when running without cats, in addition to throwing a CEL light will your computer try to adjust timing, etc to compensate??? Or is the only counteraction that pesky little light on your dash??

[GNVenom]

The protocol for OBDIII requires the PCM to attempt to "fix itself" when a code is set. To do this, it employs what's known as fuzzy logic. The PCM detects an error in the O2 post-cat circuit, and tries to fix the problem by lighting off the cat, in other words, throwing extra fuel at it. If it's successful, the CEL won't light.

If not, it will continue to throw fuel into the mix until the problem goes away. If your CEL light is on, you'll probably notice your gas mileage has gone down. That's the OBD answer to fixing the problem! Seems to increase the emissions, doesn't it? Open up the exhaust, and your MPG tanks on you.

The whole idea is, if the CEL light is on, you need to bring the car to the dealer to correct the fault. This is what the owners manual tells you. Pretty ironic isn't it??

[g-townmach]

Thanks for the plethora of info on a topic that I've always been curious about!!

[Infern0]

Oh nice explanation. Very helpful for an up and comer like myself.

With those "chambers" above, it seems doesn't throw a CEL; however, do you know if all of the "readiness" tests pass still? Based on what my last tuner was telling me, I think the states are: incomplete, failed, or ready. I think all but one or so in the "ready" state or what is needed to pass emissions here in North VA.

[14pilot]

Originally Posted by Clear Image Auto (Dan)

Yes, with the sensors removed from the direct exhaust flow, the PCM receives the correct info when comparing the before cat to after cat readings.

Nice engineering job Dan! Will this same method work for replacement downpipes on the stock manifolds, instead of using long tubes? Cat-less downpipes are a big bang for the buck IMHO. I'd like to run them and not throw codes.

[Clear Image Auto (Dan)]

Originally Posted by 14pilot

Nice engineering job Dan! Will this same method work for replacement downpipes on the stock manifolds, instead of using long tubes? Cat-less downpipes are a big bang for the buck IMHO. I'd like to run them and not throw codes.

For OFF-ROAD purposes ONLY? Ah hem. Yes. At least in our experience with other OFF Road applications.

Call for more info. I actually have the above in stock. I just haven't had a chance to advertise them yet.