emissions ready monitors, 2017 L5P

[chessy56]

So I failed my first emissions and I found that clearing a fault code resulted in resetting all of the readiness monitor flags. I've been performing the recommended GM "drive cycles" to get these all set before I take it back in for testing again. Wondering if any of the admins or techs on this page can answer some questions?
How long should it take to set all 9 of the flags? I've put on 350 miles (give/take) and thus far, 7 of the 9 are set.
Remaining is the EGR test and the filter PM test (the DPF test)- presumably, it wants to go through a regen on its own to set that flag. I forced a mobile regen but that readiness flag hasn't set, so I'm guessing that the PCM must first sense the high end of the soot level and do it's own thing in order to set the flag.

As to the EGR test, how long should that take? I'm not seeing it being set. Are more drive cycles required?

And has anyone gone through this where the emissions testing station appears to be testing readiness monitors for a gasser rather than the diesel? The diesel has some unique monitors (boost pressure, exhaust gas, DPF PM, etc.) which a gasser doesn't have. I've used 3 different scanners and they all show a different set of monitors for the diesel compared to the gas engines! Any thoughts?

[DmaxMaverick]

It isn't how many miles (in most cases) or "drive" cycles. They rely primarily on start/warm cycles (from a cold engine) for the diags to cycle. The DPF diag. needs to run on its own time, as you suspect. More mixed highway and idle and low speed (city driving) time will help with both, but primarily start/warm cycles are what you need to do.

Welcome to California (emissions)!

[More Power]

I know some here try to avoid the dealer service departments, but I'd consider it if there's a time crunch coming. They should be able to force some of the process using a Tech II.

[chessy56]

Still working on getting the remaining readiness monitors set, with 450 miles logged thus far. Soot level is around 50%. After discussing the matter with my dealership, Maverick's suggestion of letting the truck do its thing appears to be the correct course of action and, the EGR may be completed at that time. I'm told "pending codes" don't matter.

As to the difference between readiness monitors for gas vs. diesel, I'm getting the impression that the testing stations don't care (at least in Wisconsin)- perhaps they're only looking for a certain number of monitors ready (for me, it's 8 out of 9)- the actual failing monitor doesn't seem to matter being that scanners clearly show a difference.

[chessy56]

After another 350 miles and several cold starts, my EGR readiness monitor has been set. That's 8 out of 9, which should allow me to pass emissions. But after allowing the PCM to run a regen on its own, the PM Filter monitor remains "not ready". I'm going to keep running it until I get another regen to start/finish on its own and hopefully, I'll have some luck setting the remaining monitor.

[chessy56]

All set; all readiness monitors are "green". Thus far, I've accumulated 1,500 miles in this attempt; yours may be different. Most difficult to set was the PM Filter monitor as it appears that the PCM has to do a complete, uninterrupted regen on its own. You cannot force a regen manually and interrupting a regen (shutting down the truck after a regen started, and allowing the regen to resume another time) did not set the ready monitor. I had to wait for the soot level to trigger a regen and let it run on its own! Next worst was the EGR as it took miles- LOTS of miles at combined city/highway driving and take long trips if necessary. The cold startup in the morning may have something to do with how long it takes to set all monitors, but I didn't have the luxury of waiting until ambient air was within 11 deg F of the coolant temperature at each startup- which supposedly is what GM's drive cycle calls for.

It shouldn't have to be this much of a pain in the ass, but it clearly looks as if GM didn't do us any favors here. With luck, I'll pass emissions now!

[DmaxMaverick]

Sounds good, but don't blame GM for it. EPA/CARB sets the requirements and the engine series' don't get certified unless they pass their test first. All late models suffer what you did, and it doesn't get better with each passing model year. The EPA is a contradiction in terms. How many "extra" tons of C02, H0's, N0's and particulates did you generate just to get it up to their standard?

[JohnC]

I still find it ironic that the approved solution to soot (inert carbon) is to convert it into CO2 and expel it into the atmosphere by burning extra Diesel.

Better to collect it, bury it and let it turn into coal...

[EdHale]

I just had my truck washed and waxed and 2 different people asked me what the year model was. It does look real good when waxed. My signature line shows what it is and it isn't for sale and the best two things about it - It has been paid for for a long time and the LBZ engine doesn't have or require a lot of the things the newer ones require. I know it doesn't have the hp/torque of the newest models, but it tows my 5th wheel trailer great and it is and will always be bone stock. Fuel economy towing my 5th wheel works out to be 12 mpg plus or minus 0.5 mpg depending on the trip. My last check was 12.7 mpg which was 99% interstate driving with the cruise set to 62 mph.

[a5150nut]

I just had my truck washed and waxed and 2 different people asked me what the year model was. It does look real good when waxed. My signature line shows what it is and it isn't for sale and the best two things about it - It has been paid for for a long time and the LBZ engine doesn't have or require a lot of the things the newer ones require. I know it doesn't have the hp/torque of the newest models, but it tows my 5th wheel trailer great and it is and will always be bone stock. Fuel economy towing my 5th wheel works out to be 12 mpg plus or minus 0.5 mpg depending on the trip. My last check was 12.7 mpg which was 99% interstate driving with the cruise set to 62 mph.


Did the same to mine Sunday. Just turned 100k. It had 17,500 on it when I bought in December 2014. Looked for this one for the 6 speed Allison and no cow pee to deal with. When I moved from California to Tennessee i pulled my fifth wheel it scaled out at 23,500 GVW. Stopped in Nevada for a couple months, then Hurricane UT, then thru to top of the Grand Canyon going to Santa Fe NM. Just kept an eye on pyrometer and let her work. Great truck and pulls great.

[gbeaird]

Sounds good, but don't blame GM for it. EPA/CARB sets the requirements and the engine series' don't get certified unless they pass their test first. All late models suffer what you did, and it doesn't get better with each passing model year. The EPA is a contradiction in terms. How many "extra" tons of C02, H0's, N0's and particulates did you generate just to get it up to their standard?

Indeed! I 'enjoyed' this with our 2012 Caprice. Had an exhaust leak that I fixed, and reset the codes on. Since I work from home now, I don't drive much, and it took 4 months of driving to finally get the stupid montors to a ready state. Also frustrating is when you reset a single code, say, for an O2 sensor, the system sets several other monitors to not ready. One has to ask 'why'?