No way to tune around O2 sensor CEL’s?

[TheBrightSide]

Due to the recent emissions lockout, I was only knowledgeable of the fact that only standalone ECU tuning was the only other way around O2 CEL’s. And since most tuners and handheld (flash) tuners don’t offer any way to disable CEL’s and emissions-related parameters, am I stuck with my car in a “limp mode”, if I am running something like a primary cat delete, or long tube headers without cats or the secondary/downstream O2 sensors plugged in AND rigged up somehow (aside from running cats)?

I guess my only options right now, are to either run shorty headers (CARB legal) and install Solo high flow cats or stick to a 2nd cat delete; neither of these have triggered any O2 CEL’s in the past, at least for me anyways. I’m planning to run some high flow cats with my long tubes, which have O2 sensors; and I’m planning to run the downstream O2’s AFTER the cats, which should theoretically keep the O2 CEL’s off and not triggered.

I guess I could also “trick” the O2 sensors with some “simulators”, if needed, but I’m trying to currently run some high flow cats anyways. This was just in the case that I needed to have my car/engine tuned, and couldn’t be under the assumption that I had no cats (catless) or was running non-emissions level cats (sub-200 count cell high flow cats).

Anyone else have anything else to teach and/or inform me? I’ve also used old handheld tuners, but if anything, those lacked some things the new flash tuners adjusted; not to mention those also had NO way of tampering with the O2 CEL’s, so that wasn’t a viable option either….

[SlowLS1]

HP Tuners is your answer. Those codes can be disabled by it.

It can disable emission related codes, and be used to optimize performance by a skilled individual.

[Arogg]

My CEL from my lack of cats / o2s was dealt with my tuning by Trifecta. Zero issues since the tune and I pass inspection every year in NY

[gtstorey]

Originally Posted by SlowLS1

HP Tuners is your answer. Those codes can be disabled by it.

It can disable emission related codes, and be used to optimize performance by a skilled individual.

Will the newest versions of HPT disable the 2nd o2 sensor DTCs? I know that there are some emission related things that can't be turned off now, so I haven't updated in a couple of years to figure out the exact changes.

[SlowLS1]

Originally Posted by gtstorey

Will the newest versions of HPT disable the 2nd o2 sensor DTCs? I know that there are some emission related things that can't be turned off now, so I haven't updated in a couple of years to figure out the exact changes.

You can, but have to complete the compliance class first. It's available on their site, and can be found under Help/Parameter Access in the latest version.

I still use the old MPVI2 and a pretty old software version. Pretty sure this wasn't a thing then...

[Mr_Draco]

Originally Posted by SlowLS1

HP Tuners is your answer. Those codes can be disabled by it.

It can disable emission related codes, and be used to optimize performance by a skilled individual.

He's in California and disabling the codes there is a big no-no and will result in a failed inspection because they check for disabled codes.

Hopefully someone here who lives in California can chime in and give some direction on what they can and can't do.

[TheBrightSide]

Originally Posted by Mr_Draco

He's in California and disabling the codes there is a big no-no and will result in a failed inspection because they check for disabled codes.

Hopefully someone here who lives in California can chime in and give some direction on what they can and can't do.

I’m aware…. People do still use flash tuning software for offroad purposes only, so, we’ll keep it at that.

[Mr_Draco]

Originally Posted by TheBrightSide

I’m aware…. People do still use flash tuning software for offroad purposes only, so, we’ll keep it at that.

I'm aware but that wouldn't pass inspections which is what I'm assuming you are actually inquiring about. A way to do it and still pass.

[pyroguy]

What you're asking for and what you're looking for are two completely different things. The rear O2 sensors can be tuned out, but they cannot be deleted from the factory programming. At the end of the day, if you're dead set on staying in California, the best you can do is shorty headers and high flow cats. Best of luck in your quest!

[TheBrightSide]

Originally Posted by Mr_Draco

I'm aware but that wouldn't pass inspections which is what I'm assuming you are actually inquiring about. A way to do it and still pass.

Nah, I have some factory exhaust manifolds (two-piece design) to throw back on when it comes time for emissions/smog testing; bi-annual process to be able to register the car in state. I think as long as I haven’t had a CEL reset right away, it should take like 50-100+ miles of driving to properly cycle the normal emissions parameters? I know there’s EVAP and all these other things, but I’ve never failed so I think I should be fine.

I also have a spare stock set of L99 downpipes (second part of the factory exhaust manifolds/headers), but they do have a 2nd cat delete, with the cat basically gutted. No, it doesn’t throw any O2 CEL’s ofc, but I was wondering if anyone else knows if somehow I could fail otherwise, besides emissions parameters via the OBDII/ECU emission system checks? CA hasn’t used sniffers in almost over 2 decades I believe…

[silversleeper]

I didn't know they disabled the o2 on hp tuners, learn somethin new everday.
Yes they plug in and fail if there is any slightest change from stock tune, so as you might know no such thing as disable and pass. If you reflash your tune back and forth by the time you get enough smog things to say ready it will say cats fail if you don't have them. IDK if your halfcat setup will be good enough if you flash back, the second question how do you not get a cel if you go back to low perf cats will be trial and error.

[InFiD3ViL]

Wow. I had no idea this was a thing now. I knew EPA was going balls deep on some big tuners, especially the diesel guys, but this comes as a surprise.