I/M readiness: Incomplete monitors for emissions - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

TheBrightSide · 02-24-2025, 01:13 AM

I screwed up and didn't figure out my emissions earlier on, so now I have to take days or weeks even(?), to get the readiness monitors all set up for my smog check. I have an OBDII scan tool, which gives the I/M (inspection/maintenance) readiness monitors for both "last DTC's cleared" and for the current drive cycle.

For the last DTC's I cleared, I'm assuming this was also before I flashed my ECM back to factory (or so I think...) with HP Tuners. The scan tool had 4 incomplete monitors, being: catalyst, oxygen sensors, oxygen sensor heating monitor, and EVAP. The rest were mostly N/A or "OK" (not sure if that's equivalent of complete).

For the current drive cycle, it gave me 3 incomplete monitors, with EVAP, catalyst, and oxygen sensor heating monitor. Like the other chart, the rest were either N/A or read as "OK". I'm allowed to only have EVAP incomplete in my state, for gasoline vehicles of year 2000 and up.

From what I gathered online, I saw a few posts/threads on here, saying I needed to do a proper cold start for 3 minutes at least, with the rear defroster and AC on. And then I needed to drive at 55 mph for at least 3-5 minutes, and then coast all the way down to 20 mph. I know there were other posts saying you could drive 55-60 mph, but it looks like it was 55 mph and 35 mph CONSISTENTLY for 3-5 minutes, and then coasting down NATURALLY (no downshifting or braking) to either 25 mph or 1 mph. Some people even said cruise control wasn't allowed for the consistent mph part, so that's also kinda tough...

Anyways, I tried doing this all of today (deadline for smog is tomorrow; I paid reg early already) and still couldn't get the monitors to complete. For the EVAP, people said that the car had to be left alone overnight, as part of the process for it to do it's "self check" stuff while the engine is off. Not that that matters, since EVAP can be incomplete anyways... I'm gonna probably get a temporary operating permit, and then see how long I get. Some folks say if I do a mish-mash of the protocols above for anywhere from 100-500+ miles, I can at least get 2 or 3 of those monitors completed.

Joe.G · 02-25-2025, 07:57 AM

I know on the Newer GM vehicles for the Evap the Fuel tank needs to be below 3/4. Some vehicles can be a pain to get to set. I pretty much just drive them and they will eventually reset. Evap is probably going to be the last to set. I would try the start up with AC/re Defrost, Not sure if it helps or not but doesn't hurt to try it. I know it wasn't much help but I have fought these as well and Just driving it is what got it though for me.

TheBrightSide · 03-04-2025, 06:22 PM

Ended up doing a bunch of random crap for 200-250+ miles, and the permanent DTC’s cleared/reset. The I/M monitors also passed all, except for EVAP, on the “since last DTC’s cleared” drive cycle. However, I’m not sure exactly how the current drive cycle monitors work, since there was like 4-5 that were incomplete.

I ended up passing emissions testing, even with gutted secondary cats, since they don’t use sniffers for newer vehicles. I wish I had done it sooner, cause it was a matter of driving 200+ miles on 2000+ year gasoline engine vehicles, to reset existing permanent DTC’s/CEL codes. I had to get a temporary operating permit (TOP) for $50, which covers me for up to 60 days from the last registration submission deadline date.

02-24-2025, 01:13 AM	#1
TheBrightSide Drives: 2010 Chevy Camaro 2SS coupe (MT) Join Date: Jan 2024 Location: Sacramento, CA - USA Posts: 371	I/M readiness: Incomplete monitors for emissions I screwed up and didn't figure out my emissions earlier on, so now I have to take days or weeks even(?), to get the readiness monitors all set up for my smog check. I have an OBDII scan tool, which gives the I/M (inspection/maintenance) readiness monitors for both "last DTC's cleared" and for the current drive cycle. For the last DTC's I cleared, I'm assuming this was also before I flashed my ECM back to factory (or so I think...) with HP Tuners. The scan tool had 4 incomplete monitors, being: catalyst, oxygen sensors, oxygen sensor heating monitor, and EVAP. The rest were mostly N/A or "OK" (not sure if that's equivalent of complete). For the current drive cycle, it gave me 3 incomplete monitors, with EVAP, catalyst, and oxygen sensor heating monitor. Like the other chart, the rest were either N/A or read as "OK". I'm allowed to only have EVAP incomplete in my state, for gasoline vehicles of year 2000 and up. From what I gathered online, I saw a few posts/threads on here, saying I needed to do a proper cold start for 3 minutes at least, with the rear defroster and AC on. And then I needed to drive at 55 mph for at least 3-5 minutes, and then coast all the way down to 20 mph. I know there were other posts saying you could drive 55-60 mph, but it looks like it was 55 mph and 35 mph CONSISTENTLY for 3-5 minutes, and then coasting down NATURALLY (no downshifting or braking) to either 25 mph or 1 mph. Some people even said cruise control wasn't allowed for the consistent mph part, so that's also kinda tough... Anyways, I tried doing this all of today (deadline for smog is tomorrow; I paid reg early already) and still couldn't get the monitors to complete. For the EVAP, people said that the car had to be left alone overnight, as part of the process for it to do it's "self check" stuff while the engine is off. Not that that matters, since EVAP can be incomplete anyways... I'm gonna probably get a temporary operating permit, and then see how long I get. Some folks say if I do a mish-mash of the protocols above for anywhere from 100-500+ miles, I can at least get 2 or 3 of those monitors completed.

02-25-2025, 07:57 AM	#2
Joe.G Drives: 2014 2SS/RS 6SP Ashen Grey Join Date: Aug 2021 Location: NY Posts: 1,763	I know on the Newer GM vehicles for the Evap the Fuel tank needs to be below 3/4. Some vehicles can be a pain to get to set. I pretty much just drive them and they will eventually reset. Evap is probably going to be the last to set. I would try the start up with AC/re Defrost, Not sure if it helps or not but doesn't hurt to try it. I know it wasn't much help but I have fought these as well and Just driving it is what got it though for me. __________________ GM 3.91/TrueTrac OEM ZL1 Rims, 6 Piston Brakes & Side Skirts.ACST4 Splitter/Deflectors NPP M2W,GM Short Throw,GPI Ported Rod Mod,BO White PTB,CAI/JRE Scoop, GC Aluminum DS,Stainless Works Ceramic LTH/HiFlo Cats, Hotckis 1" Springs & Chassis Max Brace BMR Adjustable Swaybars,Trailing Arms, Adjustable Toe Rod, LCA & Z28 UCA Bushings Hendrix Solid Cradle Bushings Pedders Radius Rod Inserts Strut tower brace, Moroso Catch Can,SCT X4 Dynosteve,Remote Clutch reservoir,Hero Smoked Tail and 3rd Brake Light, Diode Dynamic SL1 Fog Lights AeroForce Dual gauge/Autometer pillar mount.

03-04-2025, 06:22 PM	#3
TheBrightSide Drives: 2010 Chevy Camaro 2SS coupe (MT) Join Date: Jan 2024 Location: Sacramento, CA - USA Posts: 371	Ended up doing a bunch of random crap for 200-250+ miles, and the permanent DTC’s cleared/reset. The I/M monitors also passed all, except for EVAP, on the “since last DTC’s cleared” drive cycle. However, I’m not sure exactly how the current drive cycle monitors work, since there was like 4-5 that were incomplete. I ended up passing emissions testing, even with gutted secondary cats, since they don’t use sniffers for newer vehicles. I wish I had done it sooner, cause it was a matter of driving 200+ miles on 2000+ year gasoline engine vehicles, to reset existing permanent DTC’s/CEL codes. I had to get a temporary operating permit (TOP) for $50, which covers me for up to 60 days from the last registration submission deadline date.