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Sorry, I don't understand your reply to what I was saying
Maybe I'm misreading what your statement was, you mentioned that the OBD monitoring was disabled, did you mean specifically throwing engine codes?

A scan gauge requires OBDII monitoring in order to give any sort of readout, I have a staged ECU and a scan gauge, and they both work together, giving something like 32 different monitoring options.

I did a stage 1 ECU and turboback exhaust with cat delete/lower O2 sensor delete all at the same time, I received ONE engine code, the ECU let me know that it was not receiving a reading on the lower O2 sensor, I think it was P0131-O2 sensor voltage being low, and once it threw the code one time it never came back. Basically it's the "Hey, this isn't working, letting you know this one time, just in case you didn't mean to do this" sort of warning.

But that's not from the primary O2 sensor, I'm almost positive the stage 1 only removes the input from the secondary, meaning a problem with the primary 02 sensor will still throw an engine code that the stage 1 will read.

So perhaps you meant that just certain parameters related specifically to emissions are ignored?
 

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Maybe I'm misreading what your statement was, you mentioned that the OBD monitoring was disabled, did you mean specifically throwing engine codes?

A scan gauge requires OBDII monitoring in order to give any sort of readout, I have a staged ECU and a scan gauge, and they both work together, giving something like 32 different monitoring options.

I did a stage 1 ECU and turboback exhaust with cat delete/lower O2 sensor delete all at the same time, I received ONE engine code, the ECU let me know that it was not receiving a reading on the lower O2 sensor, I think it was P0131-O2 sensor voltage being low, and once it threw the code one time it never came back. Basically it's the "Hey, this isn't working, letting you know this one time, just in case you didn't mean to do this" sort of warning.

But that's not from the primary O2 sensor, I'm almost positive the stage 1 only removes the input from the secondary, meaning a problem with the primary 02 sensor will still throw an engine code that the stage 1 will read.

So perhaps you meant that just certain parameters related specifically to emissions are ignored?
Oh okay I see what you're saying. I was referring to the 7 independent Monitors: CAT, O2, HeaterO2, Mis, Fuel, CCM, Evap, etc. that blink or don't blink depending on if they complete.
On my stage 1 pcm, I only had 4 monitors when I plugged in my OBD: HeaterO2, Mis, Fuel, and CCM...the other 3 EVAP, CAT, O2 were missing aka ”unsupported.”
And yeah like you said, I think the staged pcms only disable the downstream O2 input
 

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Yes I got a used stage 0 (nonstaged) computer that has all obd2 monitors on, repassed smog, then got my car inspected at the DMV emissions lab for them to see my emission monitors active and not ”unsupported.”
They then took the hold off my plates and i was able to register the vehicle again
Then swap back the stage 3 and enjoy the power lol. Stupid rules.

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I'm sure that's a huge relief.
Didn't realize Nevada was so strict.
California is but that's expected.
Thanks for adding creedence to my hypothesis about the Stage PCM's not monitoring Evap.
Oh, Sorry.. no the stage 3's have disabled evap monitors, and disabled cat efficiency (2nd o2 sensor) monitors. There may be more, but those two are 100% not run ever.

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Yeah staged PCMs will have 3 monitors disabled:
EVAP
CATALYST
O2SENSOR

And i think any codes associated with those monitors won't show up.
Yeah, I knew about the downstream O2SENSOR monitororing being disabled by the Stage PCM's.

But I didn't know about the CATALYST actually having a specific monitor capability for the PCM to monitor. I believe the CATALYST EFFICIENCY was monitored by the PCM checking the differences between the downstream and upstream O2 SENSOR's voltages - if the difference between the two is too small, the a CATALYTIC EFFICIENCY would be raised by the PCM.

The EVAP monitoring being disabled by the Stage PCM came as a bit of a surprise for me. But I'm still looking into it as time permits. I apparently managed to get rid of the P0440 by replacing the NVLD or so it seems. But the P0441 stubbonly remains and seems to occur at regular temporal and/or mileage intervals. I will replace the Purge Valve pending completion of a lenghty (this time) smoke test. I want to be sure that there isn't a leaking hose or connection somewhere between the gas tank and the Surge Valve. It's been warm here in NCAL so no rush on that.
 

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Yeah, I knew about the downstream O2SENSOR monitororing being disabled by the Stage PCM's.

But I didn't know about the CATALYST actually having a specific monitor capability for the PCM to monitor. I believe the CATALYST EFFICIENCY was monitored by the PCM checking the differences between the downstream and upstream O2 SENSOR's voltages - if the difference between the two is too small, the a CATALYTIC EFFICIENCY would be raised by the PCM.

The EVAP monitoring being disabled by the Stage PCM came as a bit of a surprise for me. But I'm still looking into it as time permits. I apparently managed to get rid of the P0440 by replacing the NVLD or so it seems. But the P0441 stubbonly remains and seems to occur at regular temporal and/or mileage intervals. I will replace the Purge Valve pending completion of a lenghty (this time) smoke test. I want to be sure that there isn't a leaking hose or connection somewhere between the gas tank and the Surge Valve. It's been warm here in NCAL so no rush on that.
I saw a guy troubleshoot one of the purge solenoid by applying vaccume to the vac port and tapping on the valve body. if it leaks its bad. also using a scan tool purging and closing the solenoid.. then tapping on it to see if the seat spring is weak or the diagram was torn.

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