i dunno why, but this car is hard to get the emission monitors to get to complete. i was only able to get the car to pass last year was i reflashed back to stock and was able to perform the gm drive cycle procedure after a few days of driving. this year im trying to not reflash and just keep the current tune on the car and am having difficulty to get the emission monitors to complete. i only have the o2 sensor to complete but not the o2 sensor heater as well as the other monitors. i also ensure the gas tank is between 25%-75% when i do the idling and steady foot at 20-70mph and more at 55mph. i dont have any of the emissions touched in the dtc and left the converter table stock under the engines section in hptuners. those that have their cars tuned adn able to pass inspection, any tips or advice?

 

You will never pass with a tune, that is the first thing they check, must be factory.
The EVAP test takes about 10 days of normal daily use to complete, including an overnight rest after a completed drive. Don't agonize over "drive cycle", it is all but impossible.
The O2 sensor tests run constantly. The feds say you can pass with one incomplete, unless something has changed.

When I was trying to fix a P0420 I found that immediately after the EVAP passed the catalyst test failed. Just as a data point.

 

what do you mean, 'never pass with a tune'? the inspection and emission in my state and county only look at whether the emission monitors are either complete or incomplete and if there's a cel or not-aside from the visual inspection. it's not like cali where they go further in depth to see if it has a tune .

 

If the plug into the OBD2 port they can tell.

Pa. emissions testing is based on CARB. https://www.dot.state.pa.us/public/d...ns/pub_763.pdf

 

I'm in California, I passed with a tune from ZZP.

New engine, Opel injectors, new ZZP LNF downpipe and the tuned ECM were installed by me 2.5 years ago. No problem passing smog check at that time.

2 years later(a few months ago), most of the monitors would complete, no problem. The EVAP was very difficult to complete. It eventually did complete by successfully completing drive cycles.

The Catalyst test absolutely would not complete. I was replacing parts out of desperation. I eventually put the original downpipe and catalytic converter back on. Shortly thereafter, the Catalyst test completed, and I got my smog certificate.

So the ZZP LNF downpipe catalytic converter lost its efficiency rather quickly.

https://www.chevyhhr.net/forums/prob...g-check-65465/

The hardest part of the drive cycle was driving the car 1,200 - 1,500 RPM for 2 minutes. Find a nice FLAT country road and drive for more than the 2 minutes.

 

According to my recent search Cal. has banned all tunes. Don't know the specifics.

 

Beginning July 19, 2021, vehicles with software not provided by the original equipment manufacturer (OEM) or approved through a California Air Resources Board (CARB) Executive Order (EO) will fail Smog Check.

And yet my vehicle passed...

 

thanks RJ_RS_SS_350. i guess i'll need to drive and hold steady throttle between those RPMs for longer than 2 min. i had thought i did that on the freeway going a steady 55mph but maybe i was out of RPM range or maybe not enough key cycle turns before pcm would start to track that test. my state and/or county doesnt or hasnt banned tunes yet plus i have my buddy mechanic who would be ok with an aftermarket tune just so long the emission monitors read complete.

 

It's unclear from your post, which monitors are not complete. Everything except EVAP and CAT completed without even trying.

55 MPH is too high RPM for the part of the drive cycle I was referring to. Ask your mechanic to print out the drive cycle for your VIN.

 

the only emission monitor that completed was the o2 sensor. the other ones are incomplete: catalyst, evap system, o2 sensor heater, and egr