21NE and GMC Canyon

[Johnspierce]

Thanks for all this information guys. I don’t pretend to understand all of it, but the discussion helps! I’m waiting for GMC to do a big rebate or something to the dealers.

[JeffreyG]

Originally Posted by splitting_lanes

It’s my understanding that some parts of the ATS system are required, and if they fail the engine won’t run, not because it can’t run, but because it’s programmed that way.

California has pushed OBD for diesel on-highway engines since 2013. The vehicle has to diagnose itself, and if it determines that various parts of the emissions control systems are not working, lamps are illuminated.

I'm not sure how aggressive the systems are on gasoline engines these days, but a few parts of the diesel systems can render the vehicle inoperable if they have failures which are not resolved.

One of the big reasons for this is that when we told the regulators that we planned to use SCR back in the early 2000's, they became convinced that operators would fail to fill the DEF tank or would fill it with distilled water etc. So SCR faults can put a vehicle into "final inducement" after several warnings, leaving you on foot. But you will get a lot of warnings before you are walking.

This understanding may be something I deduced by reading about delete and/or defeat systems — which I’m not interested in doing, unless it comes down to being able to make it to a repair shop.

The EPA has put these aftermarket defeat device purveyors out of business, but so far Canadians can still buy them. Too many people were too obvious selling "Non-road use only" items to a customer base that was 99.99% using them on-highway.

Now I’m curious as to what improvements can be made to the ATS so that it doesn’t shorten the life of the engine, and what systems in the ATS will fail first, or not fail at all.

The ATS won't hurt the engine, but major engine problems can kill the ATS. Some examples would be anything that sends fuel, oil, or coolant down the exhaust pipe. These liquids can poison or flat out burn/melt the catalysts.

Anything that can make an engine run smokey, like a boost leak, can also kill the DPF. I monitor boost levels.

So what can go wrong with the ATS? Most likely:
1) One of the two NOx sensors, the soot sensor, and the DEF injector. Bad sensors can lead to interesting tail chasing. A bad NOx sensor will give a code like "DEF quality low" because again, EPA thought operators would put water in the tank. But that isn't likely and the problem is way more likely to be a bad NOx sensor. Those things are not super reliable.

2) The DPF loading up with ash. Do not run engine oil with sulphated ash content over 1%. I personally avoid biodiesel too because that industry is still for the most part wild-wild-west.

Biodiesel is like a box of chocolates, you never know what you're going to get.

I feel like we should start a new thread just to discuss ATS, so if you want to... do it, and I’ll ask questions, and I’m sure others will too. It’s great to have these discussions with someone who understands these systems.

We're lucky these systems are now reaching maturity. Speaking for HD diesel but knowing passcar systems were in similar timeframe, EGR hit the market in 2002, DPF's in 2007, and SCR in 2010. Some of this stuff didn't work great at first.

I don't know on the passcar side, but these days the EGR systems are pretty trouble free for HD.

Best thing to do with these light-duty diesels is run them. Long highway drives are happy. Lots of short trips will likely have the engine running some kind of sloppy, wet, low NOx / high EGR warm up mode. Our HD trucks work great in the most predictable market - long haul trucks moving freight.

[Johnspierce]

Originally Posted by JeffreyG

Best thing to do with these light-duty diesels is run them. Long highway drives are happy. Lots of short trips will likely have the engine running some kind of sloppy, wet, low NOx / high EGR warm up mode. Our HD trucks work great in the most predictable market - long haul trucks moving freight.

Sounds like a great combo for pulling an Escape in retirement!

[salmo7000]

Originally Posted by Johnspierce

Sounds like a great combo for pulling an Escape in retirement!

Yep, I'm totally into this discussion, but my comment is a simple one. I am most definitely not a mechanic or engineer. I have a 2017 Colorado Duramax. So far it's been an excellent tow for my 19. I mostly drive highways in rural Idaho and Montana with lots of steep grades, which it seems to like. I've noticed it performing a regen cycle on the DPF exactly 0 times since I've owned it. I assume it's doing its thing and not having any trouble doing it. Hopefully that's a good assumption

I dump 2.5 gallons of DEF into it when it tells me it needs it and have performed scheduled maintenance exactly per the specifications in the owners manual. Other than new tires, that's all I've done to it. I've driven it almost 48,000 miles, at least 10,000 towing, without a lick of trouble. Of course this is no guarantee I won't have trouble, just that I haven't yet.

If the thing ever blows up on me and leaves me stranded with a hugely expensive repair bill, I'll gladly report it here. But so far, so good!!

[cpaharley2008]

I used to own a Jeep Liberty Common Rail Diesel (crud) was the nickname and towed about 50,000 miles before giving it away. Oil changes were $$$ and mileage was horrible.

[JeffreyG]

Originally Posted by cpaharley2008

I used to own a Jeep Liberty Common Rail Diesel (crud) was the nickname and towed about 50,000 miles before giving it away. Oil changes were $$$ and mileage was horrible.

Crazy story about that engine.....in the 1990's a company called VM Motori in Cento Italy was selling a 2.5L I-4 engine to Chrysler for European minivans and Jeeps. The engine was a real unusual one with tunnel crank, wet liners, and individual pot heads.

My company owned VM Motori in 2000, and I spent some time working on a project to put a version of that engine (now with slab aluminum head and common rail injection) in another OEMs European market SUV. The project was cancelled. Around then, VM designed a bigger displacement 2.8L version.

We were acquired by a giant German company, VM Motori stayed with the previous owner, so I didn't work with them again. The company was eventually acquired by Stellantis and is still owned by Stellantis.

The VM engine again surfaced in the 2005-2006 CRD Jeep. I still see some versions of it in Stellantis products.

Somewhere in there, GM acquired design ownership of a version of the VM Motori 2.8L engine. This is the GM LWN engine. I have looked at pictures of the engine and it both unmistakably is the VM engine, and it is also unmistakably changed a ton. So......interesting.

The LWN doesn't have any of the weird stuff.....no tunnel crank, no wet liners, no pot heads. It has a much better cam belt (150k miles, that was 72k miles back in 2001). The GM engine uses a Denso FIS, the VM and Stellantis versions of the engine have always been Bosch so far as I can see.

It's actually interesting. I recognize the engine, but clearly GM did a lot of work on it. Plus the LWN is assembled in Thailand, not Cento, Italy.

[splitting_lanes]

Originally Posted by JeffreyG

California has pushed OBD for diesel on-highway engines since 2013. The vehicle has to diagnose itself, and if it determines that various parts of the emissions control systems are not working, lamps are illuminated.

I'm not sure how aggressive the systems are on gasoline engines these days, but a few parts of the diesel systems can render the vehicle inoperable if they have failures which are not resolved.

One of the big reasons for this is that when we told the regulators that we planned to use SCR back in the early 2000's, they became convinced that operators would fail to fill the DEF tank or would fill it with distilled water etc. So SCR faults can put a vehicle into "final inducement" after several warnings, leaving you on foot. But you will get a lot of warnings before you are walking.


The EPA has put these aftermarket defeat device purveyors out of business, but so far Canadians can still buy them. Too many people were too obvious selling "Non-road use only" items to a customer base that was 99.99% using them on-highway.


The ATS won't hurt the engine, but major engine problems can kill the ATS. Some examples would be anything that sends fuel, oil, or coolant down the exhaust pipe. These liquids can poison or flat out burn/melt the catalysts.

Anything that can make an engine run smokey, like a boost leak, can also kill the DPF. I monitor boost levels.

So what can go wrong with the ATS? Most likely:
1) One of the two NOx sensors, the soot sensor, and the DEF injector. Bad sensors can lead to interesting tail chasing. A bad NOx sensor will give a code like "DEF quality low" because again, EPA thought operators would put water in the tank. But that isn't likely and the problem is way more likely to be a bad NOx sensor. Those things are not super reliable.

2) The DPF loading up with ash. Do not run engine oil with sulphated ash content over 1%. I personally avoid biodiesel too because that industry is still for the most part wild-wild-west.

Biodiesel is like a box of chocolates, you never know what you're going to get.


We're lucky these systems are now reaching maturity. Speaking for HD diesel but knowing passcar systems were in similar timeframe, EGR hit the market in 2002, DPF's in 2007, and SCR in 2010. Some of this stuff didn't work great at first.

I don't know on the passcar side, but these days the EGR systems are pretty trouble free for HD.

Best thing to do with these light-duty diesels is run them. Long highway drives are happy. Lots of short trips will likely have the engine running some kind of sloppy, wet, low NOx / high EGR warm up mode. Our HD trucks work great in the most predictable market - long haul trucks moving freight.

Great information here. Good to know my plan to put an air/oil separator on the cv is a good one (to keep the mist out of the intercooler and ATS/sensors/mixing with EGR soot).

Where would you get a boost leak? The intercooler or a hose to/from it?

Should I install a boost gauge? Is the boost available via ODB?

I’m looking forward to towing with it, and generally using it for all the trips my electric car can’t make. So I guess I’m the right use case for it, just gotta wait until next March for the trailer.

[JeffreyG]

Originally Posted by splitting_lanes

Where would you get a boost leak? The intercooler or a hose to/from it?

Charge air coolers can crack, but these passenger car diesels don't seem to run over about 2.5 bar boost much. I'd say leaks at hose and pipe joints are the most likely spots.

Should I install a boost gauge? Is the boost available via ODB?

The OBD II port has most all information you might want. There are cheap plug in Bluetooth units, you plug them into the port and link them to your phone.

I went a little more expensive with a Banks iDash because I could put it in a 53mm gage pod, which you can make up special as a drop in on the defroster vent like this. Just need a 3D printer.

The iDash can display things various ways, I just have it set to the max (8 channels) at a time. You can see here I'm reading:


Requested Torque %
Calculated HP
Boost Pressure
EGR Temperature (which is turbine inlet temperature)
Gear and TC lockup status
Engine Oil Temperature
DPF Filled %
Active Regeneration Status

[splitting_lanes]

Originally Posted by JeffreyG

Charge air coolers can crack, but these passenger car diesels don't seem to run over about 2.5 bar boost much. I'd say leaks at hose and pipe joints are the most likely spots.

The OBD II port has most all information you might want. There are cheap plug in Bluetooth units, you plug them into the port and link them to your phone.

I went a little more expensive with a Banks iDash because I could put it in a 53mm gage pod, which you can make up special as a drop in on the defroster vent like this. Just need a 3D printer.

The iDash can display things various ways, I just have it set to the max (8 channels) at a time. You can see here I'm reading:


Requested Torque %
Calculated HP
Boost Pressure
EGR Temperature (which is turbine inlet temperature)
Gear and TC lockup status
Engine Oil Temperature
DPF Filled %
Active Regeneration Status

That gauge is awesome! There’s like 100+ things you can track on a Chevy Colorado, I’d assume the same on a canyon. Keeping an eye on transmission temperature would be real handy while towing, in addition to many other temp and load related things.

I have an OBD Bluetooth adapter for my car, but I don’t have a map of the sensors for the Canyon... well, I assume I need some sort of mapping to be able to tell what point you’re looking at. For my leaf I have the leafspy app on a phone, gives me an interface for diagnostic and reprogramming stuff like the door locks. A quick perusal of google didn’t yield anything useful for a canyon/Colorado. Edit: looks the the App Store has a bunch, guess I’ll check one out.

My wife seems to enjoy driving it so far, we bought it as a replacement for her Toyota SUV, and of course to tow with.

2.5 bar is almost 40psi! Yikes, that’s some boost.

[JeffreyG]

Originally Posted by splitting_lanes

That gauge is awesome! There’s like 100+ things you can track on a Chevy Colorado, I’d assume the same on a canyon. Keeping an eye on transmission temperature would be real handy while towing, in addition to many other temp and load related things.

Transmission temperature is actually one of the data displays that you can read directly from the DIC (drivers information center) in the center of the cluster. So GM actually gives you a read for that one without using an OBDII reader.

I have an OBD Bluetooth adapter for my car, but I don’t have a map of the sensors for the Canyon... well, I assume I need some sort of mapping to be able to tell what point you’re looking at.

If you pull up the users manual for the Banks iDash you can see all the channels possible to read. Most of them are intuitively obvious. The ones that are not are mostly exhaust temperatures (there are several along the whole ATS system) but I figured out that EGR temp 1 is EGR inlet temperature, which is the same as turbine inlet temperature.

2.5 bar is almost 40psi! Yikes, that’s some boost.

Diesel engine boost is typically much, much higher than anything you would see on an SI gasoline engine. To me, normal boost ranges would be up to 3 bar. For a while when EGR came along some people tried running really high boost with really high EGR rates, and so some engines were around 4.5-5 bar. But you can't easily make that kind of pressure across a singe compressor wheel, so you need two stages.

Then again, two stage compressor with interstage charge air cooling is really efficient. Not that anyone has put something like that into production.

[Brian B-P]

Originally Posted by splitting_lanes

I kinda figured maybe GM doesn’t want these things to last as long as they potentially could... can’t sell a new truck to someone that can get a half million miles on the one they got.

Originally Posted by JeffreyG

It's not so much an engineered obsolescence as it is that a vehicle has to have cost and life targets. So you can't make everything cost too much so that the vehicle lasts 500,000 miles. Nobody would buy it because it would be too expensive.

Not only would almost no one buy it, but the ones who did buy it new would still replace it at a few years old anyway to get a newer one with trendier toys on the dash. Half million mile life corresponds to decades of ownership in a consumer vehicle, and is pointless for the vast majority of potential buyers.

[NEWYORKHILLBILLY]

Next year I plan on getting a new tow rig. I was thinking a f150 But this thread got me interested in the canyon or Colorado. My late Father was a GM tool and die maker for 35 years. I never owned a Diesel and know nothing about them. These trucks seem to be perfect match for a escape.

[stephen99]

Originally Posted by NEWYORKHILLBILLY

Next year I plan on getting a new tow rig. I was thinking a f150 But this thread got me interested in the canyon or Colorado. My late Father was a GM tool and die maker for 35 years. I never owned a Diesel and know nothing about them. These trucks seem to be perfect match for a escape.

I've enjoyed pulling our 21 with a diesel Canyon for the past 3+ years. On level ground it can do 20 mpg. No problem going up or down mountains. You do have to add DEF every once in a while but that's no big deal. It comes in 2.5 gallon jugs available at Walmart or Home Depot for about $12.

[splitting_lanes]

Originally Posted by JeffreyG

Transmission temperature is actually one of the data displays that you can read directly from the DIC (drivers information center) in the center of the cluster. So GM actually gives you a read for that one without using an OBDII reader.



If you pull up the users manual for the Banks iDash you can see all the channels possible to read. Most of them are intuitively obvious. The ones that are not are mostly exhaust temperatures (there are several along the whole ATS system) but I figured out that EGR temp 1 is EGR inlet temperature, which is the same as turbine inlet temperature.



Diesel engine boost is typically much, much higher than anything you would see on an SI gasoline engine. To me, normal boost ranges would be up to 3 bar. For a while when EGR came along some people tried running really high boost with really high EGR rates, and so some engines were around 4.5-5 bar. But you can't easily make that kind of pressure across a singe compressor wheel, so you need two stages.

Then again, two stage compressor with interstage charge air cooling is really efficient. Not that anyone has put something like that into production.

I think I’m going to need to get one of those gauges. Did you route the wire through the vent?

Also, do you have a link to the file? I don’t have a 3D printer, but I can ask around....

[JeffreyG]

Originally Posted by splitting_lanes

I think I’m going to need to get one of those gauges. Did you route the wire through the vent?

Also, do you have a link to the file? I don’t have a 3D printer, but I can ask around....

The wire just drops into the dash between the vent cover and the vent tubing, and then it is easy to route it to the OBD port that is near the parking brake pedal. Very tidy.


There are guys that will print you these gage pods no problem (if a little bit pricey). They usually operate off FB pages or whatever which seems sketchy but I have seen people getting products no problem online. Like this guy:


https://www.facebook.com/Block8head/

[MB Walker]

A bit of a thread hijack to take advantage of your engineering expertise... we tow with a Silverado 1500 5.3 V8 gasoline direct injection engine. That type of injection is after the intake ports, so there is no fuel to keep the intake valves clean. I know GM has done some work to separate the oil out of the EGR airstream, but some swear by aftermarket catch cans to aid in this. I’ve read, short of that, keep the oil clean- change at 5000 regardless, don’t let the engine idle unnecessarily, don’t take short trips.

Am I on the right track? Is a catch can a good addition? Thanks in advance,
Mac

[JeffreyG]

Originally Posted by MB Walker

A bit of a thread hijack to take advantage of your engineering expertise... we tow with a Silverado 1500 5.3 V8 gasoline direct injection engine. That type of injection is after the intake ports, so there is no fuel to keep the intake valves clean. I know GM has done some work to separate the oil out of the EGR airstream, but some swear by aftermarket catch cans to aid in this. I’ve read, short of that, keep the oil clean- change at 5000 regardless, don’t let the engine idle unnecessarily, don’t take short trips.

Am I on the right track? Is a catch can a good addition? Thanks in advance,
Mac

I wonder to some extent if a lot of the hand wringing and catch can sales are driven by the appearance of 'gunk' that isn't harming anything. Some goo in the intake or on the valve stems isn't going to affect the engine much. I have not seen or heard of significant problems with deposits on valves since we started running EGR on engines in 2002.

Accelerating oil drain intervals doesn't seem likely to make much difference. Any deposits forming are likely to be a mix of oil mist with soot from the EGR. I can't imagine why a little bit older oil would make much difference either way.

Catch cans are pretty low risk. They have the downside of costing some money and they do come with a small risk. It's best to use a can with a safety vent, and keep the hose routing short plus avoid making a plumbing trap in the hose. If the vent or the piping collect water and it freezes, the CCV can become blocked to flow. This will pressurize the crankcase and blow out the main crankshaft seal.

To me, the key items you normally are trying to keep clean of mist are the compressor wheel and the charge air cooler. Your engine has neither of these. You also want to avoid burning oil mist in an engine with a DPF, but again, your engine doesn't have one.

Overall I have to defer to people with direct experience with high mileage 5.3L V8's. I'm surprised the CCV + EGR causes problems but I can't say it's impossible that it might.

[splitting_lanes]

Originally Posted by JeffreyG

The wire just drops into the dash between the vent cover and the vent tubing, and then it is easy to route it to the OBD port that is near the parking brake pedal. Very tidy.


There are guys that will print you these gage pods no problem (if a little bit pricey). They usually operate off FB pages or whatever which seems sketchy but I have seen people getting products no problem online. Like this guy:


https://www.facebook.com/Block8head/

Where did you get your gauge pod from? Looks like Block8head is a couple months behind on orders currently....

Thanks for all the information, especially about emission systems, it seems the only information you can get about them is coming from people that want to sell you something to remove it. Bad for your wallet and the environment.

[JeffreyG]

Originally Posted by splitting_lanes

Where did you get your gauge pod from? Looks like Block8head is a couple months behind on orders currently....

I was vague because I didn't want to endorse anyone, but I got mine from Block8head. He was claiming a huge backup in December, but I got the part in ~3-4 weeks anyway. YMMV.

No complaints on the part, strong and looks good.

Thanks for all the information, especially about emission systems, it seems the only information you can get about them is coming from people that want to sell you something to remove it. Bad for your wallet and the environment.

Well, I spent a decade creating these ATS systems for class 8 diesel trucks in North America. We did EGR in 2002, DPFs in 2007, and SCR in 2010. I was directly involved in all of that.

I get it that nobody wants more cost, more complexity, more opportunity for failure down the road. But then I also thought it was ridiculous that there were so many 'tuners' essentially selling defeat devices to regular, on-road users under the guise of 'race use only' or 'off-road use only'. I get it that people don't want the complexity. But turning a blind eye to what was going on was kind of interesting and eventually the regulators did react. EPA started suing the tuners in 2019 and I don't think there are any companies selling defeat devices on a large scale across the country. To do so is to invite a lawsuit from EPA. What remains are the tuner equivalent of the guy in a trench coat saying "Hey, wanna buy a Rolex?" on the street.

Canada adopts US regulations, but they have not gone after defeat devices. So if you live in Canada you can revert to 1986 emissions levels. But I hear you have to prove to the tuners that the truck is domiciled in Canada.

There are still tuners selling products, but they have to submit emissions data. That means they are essentially facing the same trade offs as the OEM. One area perhaps they can make improvement is in shaving off margin, knowing they probably won't get audited by ARB. Or they are making different tradeoffs because they maybe don't know what some limits are, or they can't measure them (likely). I mean.....are these guys really measuring cylinder pressure and tracking rates of heat release? Some of the old tuner stuff my friends at Bosch showed me suggest they are not.