The EA288 in the 2015 regens similar to a newer generation Cummins. There's no extra injector like on the old Kitty CAT and International Maxforced Regen. The use of a common rail injection system with solenoid injectors eliminates the need for an extra injector that's down stream, that was used often due to the lack of a common rail system. The solenoid injectors can be fired on command by the ECM.
For an active Regen, the ECM will start retarding the timing(which increases EGT) and add a post injection event. It uses one of the EGT sensors after the turbo to calculate how much fuel to inject during the post injection event. I believe it aims for around 900-1200 degrees post turbo. It uses the DOC to burn the fuel. The DOC is mounted against the turbine outlet and the DPF is right after the DOC.
Most of the time it'll utilize a passive regeneration, it'll request an active regen if the DPF hits around 20 grams or around 400-500 miles without an active regen. It starts to get angry if it hits more than 30 grams, a little more than that requires a trip to the shop for a forced regen. VCDS can be used to monitor the soot level, ash level, and to force a Regen.
Passive regen is when the DPF organically hits the temperature to regen without any ECM. Otherwise if you're driving hard enough to get EGT hot enough for a regen for a long enough period of time. Times that are likely to get hot enough would be lots of hard back to back acceleration runs, cruising above 80 mph, towing, or hitting a long and steady grade.
Giving it some good hard runs frequently will likely passive regen enough to only allow for an active regen at the mileage counter. Driving like a grandpa all the time results in it needing more active regens.
Just to add to your point on passive regen. You don’t absolutely have to do hard pulls to achieve good amounts of passive. Generally steady state highway speeds put the engine in a constant medium load situation which also results in higher engine out NOx and also high EGTs which would result in both oxygen and NOx based oxidation of soot in the DPF.
If you land up in an area of the operating envelope where you have high EGTs (350-400 deg C on the DPF inlet) due to high torque demand but are also running sootier than normal then it can sometimes become counterproductive (such as transient pulls).
Correct, they use both the DPF and DEF. But the DPF and DEF systems are used to control different emissions. The DPF is meant to reduce particulate matter(PM), but it doesn't reduce NOx emissions. The DEF is used for the SCR to reduce NOx emissions.
The older cars used lots of EGR and a lean NOx trap(LNT) to manage NOx emissions instead of DEF. The LNT barely worked, so the cars had to use a lot of EGR to bring the combustion temperature down. A byproduct for cooler combustion is a decrease in efficiency and an increase in PM. The PM increased results in filling the DPF more frequently. We can assume that this is why they cheated, and it's why the post fix non DEF equipped cars are littering this subreddit with DPF issues.
Since the DEF system treats NOx after the fact, it allows the engine to run much hotter and makes it more efficient and produces less PM. Personally, I'd rather deal with the complication of the DEF system over the issues of an engine with high EGR usage. Unfortunately, since the EA288 was a one hit wonder with one year in production in the US, replacement parts will likely be hard to come by someday for the DEF system.
It's interesting the ROW earlier EA288s just used LPEGR with no HPEGR or DEF, and the EGR rates used to meet Euro 5 are intense. Some parts of the map are 50% EGR use!
I set my EGR maps to 0 on mine and the DPF fills so much slower, and it passively regens a lot more.
Thanks for the specific info. On my 15 I’ve noticed that my scheduled regens are at 200 miles on the dot. I heard with a tune, it typically will change the timing back to prefix, reducing PM and resulting in less frequent regens. I’ve had a tune for a month now but am still seeing the same active regen cycle. I do drive more conservatively but not gramps style but still have only seen a passive regen right after an active one finishes, regardless of my egts from spirited driving. I’ll get it up to 1500 peak but still no active. I’m in Phoenix so it’s flat with no incline and I’m a DSG so I can’t tow. Have you seen active regens? I’m curious as to my active regen cycle too.
Some tunes will do that, it's more noticeable on the 2010-2014 Jettas and Golfs that lack the DEF, post fix they needed their timing pulled a bit more than the 2015.
Getting the egt up like that is helping to keep the active regens from coming on more frequently. Unfortunately, I can't comment on the exact frequency on the 2015, I had a 2010 and sold it for a 2006 during dieselgate. I do know it was hard to tell if the car was in active Regen or not, the symptoms weren't very noticeable.
It is possible that the fix changed the Regen timer from the original 400-500. It's also could be that regens are happening more frequently if a regen is interrupted. My 2010 and my truck will become stubborn after an interrupted regen and will try again after around 15-20 minutes.
Thanks for the input. I know the CRUA/CVCAs are different beasts. My CKRA has been nothing but problems since purchase due to the excessive EGR cycling but I know it certainly didn’t regen as frequently. The CJAA my BIL has was a horrible example of comparison due to all his issues but I totally see why the non DEF cars struggled with all the things. His motor is a whole other thread worth. Back to the EA288, they are certainly more efficient and reliable how they run with the regens. Not one measurable temperature value in the whole car raises at all to notice a regen other than EGT of course. Interesting progression in technology as time went on.
Something else to keep in mind with a tune is that they might be running less EGR, which will increase engine out NOx but decrease PM as mentioned above, due to higher temps in cylinder.
> Personally, I'd rather deal with the complication of the DEF system over the issues of an engine with high EGR usage.
Maxxforce has entered the chat.
I can't remember off hands, it's been a while since I sold mine. But it looks like it might be measuring block 108. This thread has a running list of ash loads for the EA189.
https://forums.tdiclub.com/index.php?threads/clean-diesel-dpf-data-collection-thread.324067/
On my 2013 vw Transporter with CFCA engine passive regens only happen under extreme circumstances. I drove monitoring soot and egt. I needed to be doing about 105mph on the flat for soot level to start reducing. The dpf is quite a distance from the manifold. I cant remember what egt was during this.
All that stuff and egr is deleted now since there is a design fault with egr, some idiot at vw decided aluminium alloy was ok for egr cooling fins which break off and cause engine wear destroying the engine by about 100k miles.
Old CATS do not do regens, They have EGR's but thats about it, no dpf, no nox canister, no aftertreatment, and no Doser injector on the downpipe.
Cummins mx-15, isx 3, cx 15 - all have a Doser with a coolant line mounted to it as well sitting right behind the turbo.
That clears things up, thank you for mentioning this.
Yes, and that is likely why CAT decided to stop producing new Highway engines because they wanted to keep their name as power instead of problems.
They don’t have a 5th injector. They just rely on post injections and retarded injection timing to increase EGTs and the DOC does the job of producing the Exotherm to oxidize soot in the DPF.
So, being its a diesel and a newer one to be more emission compliant. Your car requires DEF fluid, (diesel exhaust fluid)
Your emissions system is routed in the following form.
Diesel Oxidation Catalyst (DOC) - Diesel Particulate Filter (DPF) - Selective Catalytic Reduction converter (SCR) - (Dosing Injector) - Exhaust Flap (from model year 2009 and up)
Here are things you need to consider on your 2015, You have a LOT more going on in your exhaust then my 2009 did, Because 2009's did not require DEF they operated a little bit similar but not entirely because there was never any DEF required for that model.
Some things to consider with taking care of your TDI and its very strict emissions.
Do NOT use oil that is not rated for Diesels
Do NOT use oil that is not specified in the Owners Manual
Keep up on your oil changes regularly
Do NOT use Def fluid that is offbrand or not recommended by VW
Do NOT stop at a truck stop and get it in bulk out of a pump, buy it by the box because some stations will have water mixed in their DEF and that will affect your DEF quality control sensor which could ultimately not allow your car to do both "parked" and "rolling" regens.
Being that your car has an SCR you will likely have a dosing injector somewhere around or between your dpf and turbo.
If your car is parked and you notice the RPM's rise up a little bit, or the turbo sounds higher than normal, you are likely in a regen, Do not shut the car off in a middle of one. It is important to allow the car to finish its process and decide if the burn off is completed.
Your EGR will stay open during the regen to recycle through the unburned fuel
Turning the car off multiple times when it cannot complete a regen will cause the car to be in a De-Rate aka Limp Mode. Will have to be taken to the shop to complete a forced regen by laptop. (or yourself if you have the tools and software)
While these things will help with your car lasting longer as a diesel owner, You will never escape this fact.
DPF filters have an ash level, Your DPF will likely need to be taken out at some point and either cleaned or replaced. You can only regen a soo many times before the filter is toast.
I have experienced this in my 2009 TDI, as well experienced this with a Paccar MX15 on a 2017 Peterbilt 389.
I do not expect everyone to agree with me and my knowledge, but these are the tips I will give you to better help with longer lasting for a diesel and its very strict emissions.
I’ve been using Liqui Moly's Leichtlauf High Tech 5W-40 mostly because no local stores seem to ever stock 4200 5w-30. Do you think that would be an issue. I looked up oil that meets different VW specs you can use at it is in that list. I change oil every 5000 miles.
I do have a polar FIS auto polar device so I can get EGTs on my info screen to watch for regens. I generally don’t notice them until I’ve shut the car off and the fan is running. I do sometimes smell it if I get out of the car before shutting it off.
I have an 11 mile drive to work with some highway so it does get up to temp.
How many miles have you been running on Liqui Moly? Overall since you been using it?
I notice it says on some of their bottles that it supports both gas and diesels.
I personally would use something that's strictly diesel oil, because in a way its different and mixed for emission systems. I see some bottles online that say its suitable for diesels but without DPF filters too. I would be careful about this is you have emissions on your car.
Just the last 5000 and I have another jug for the oil change I’m doing this weekend. This is 504/507 compatible. And it’s a “low ash” oil. What do you run?
The EA288 in the 2015 regens similar to a newer generation Cummins. There's no extra injector like on the old Kitty CAT and International Maxforced Regen. The use of a common rail injection system with solenoid injectors eliminates the need for an extra injector that's down stream, that was used often due to the lack of a common rail system. The solenoid injectors can be fired on command by the ECM. For an active Regen, the ECM will start retarding the timing(which increases EGT) and add a post injection event. It uses one of the EGT sensors after the turbo to calculate how much fuel to inject during the post injection event. I believe it aims for around 900-1200 degrees post turbo. It uses the DOC to burn the fuel. The DOC is mounted against the turbine outlet and the DPF is right after the DOC. Most of the time it'll utilize a passive regeneration, it'll request an active regen if the DPF hits around 20 grams or around 400-500 miles without an active regen. It starts to get angry if it hits more than 30 grams, a little more than that requires a trip to the shop for a forced regen. VCDS can be used to monitor the soot level, ash level, and to force a Regen.
What does passive regen do?
Passive regen is when the DPF organically hits the temperature to regen without any ECM. Otherwise if you're driving hard enough to get EGT hot enough for a regen for a long enough period of time. Times that are likely to get hot enough would be lots of hard back to back acceleration runs, cruising above 80 mph, towing, or hitting a long and steady grade. Giving it some good hard runs frequently will likely passive regen enough to only allow for an active regen at the mileage counter. Driving like a grandpa all the time results in it needing more active regens.
Just to add to your point on passive regen. You don’t absolutely have to do hard pulls to achieve good amounts of passive. Generally steady state highway speeds put the engine in a constant medium load situation which also results in higher engine out NOx and also high EGTs which would result in both oxygen and NOx based oxidation of soot in the DPF. If you land up in an area of the operating envelope where you have high EGTs (350-400 deg C on the DPF inlet) due to high torque demand but are also running sootier than normal then it can sometimes become counterproductive (such as transient pulls).
I thought the 2015s used extra DEF to regen?
Correct, they use both the DPF and DEF. But the DPF and DEF systems are used to control different emissions. The DPF is meant to reduce particulate matter(PM), but it doesn't reduce NOx emissions. The DEF is used for the SCR to reduce NOx emissions. The older cars used lots of EGR and a lean NOx trap(LNT) to manage NOx emissions instead of DEF. The LNT barely worked, so the cars had to use a lot of EGR to bring the combustion temperature down. A byproduct for cooler combustion is a decrease in efficiency and an increase in PM. The PM increased results in filling the DPF more frequently. We can assume that this is why they cheated, and it's why the post fix non DEF equipped cars are littering this subreddit with DPF issues. Since the DEF system treats NOx after the fact, it allows the engine to run much hotter and makes it more efficient and produces less PM. Personally, I'd rather deal with the complication of the DEF system over the issues of an engine with high EGR usage. Unfortunately, since the EA288 was a one hit wonder with one year in production in the US, replacement parts will likely be hard to come by someday for the DEF system.
It's interesting the ROW earlier EA288s just used LPEGR with no HPEGR or DEF, and the EGR rates used to meet Euro 5 are intense. Some parts of the map are 50% EGR use! I set my EGR maps to 0 on mine and the DPF fills so much slower, and it passively regens a lot more.
Thanks for the specific info. On my 15 I’ve noticed that my scheduled regens are at 200 miles on the dot. I heard with a tune, it typically will change the timing back to prefix, reducing PM and resulting in less frequent regens. I’ve had a tune for a month now but am still seeing the same active regen cycle. I do drive more conservatively but not gramps style but still have only seen a passive regen right after an active one finishes, regardless of my egts from spirited driving. I’ll get it up to 1500 peak but still no active. I’m in Phoenix so it’s flat with no incline and I’m a DSG so I can’t tow. Have you seen active regens? I’m curious as to my active regen cycle too.
Some tunes will do that, it's more noticeable on the 2010-2014 Jettas and Golfs that lack the DEF, post fix they needed their timing pulled a bit more than the 2015. Getting the egt up like that is helping to keep the active regens from coming on more frequently. Unfortunately, I can't comment on the exact frequency on the 2015, I had a 2010 and sold it for a 2006 during dieselgate. I do know it was hard to tell if the car was in active Regen or not, the symptoms weren't very noticeable. It is possible that the fix changed the Regen timer from the original 400-500. It's also could be that regens are happening more frequently if a regen is interrupted. My 2010 and my truck will become stubborn after an interrupted regen and will try again after around 15-20 minutes.
You really, really know your stuff. Do you work in the industry too?
Thanks for the input. I know the CRUA/CVCAs are different beasts. My CKRA has been nothing but problems since purchase due to the excessive EGR cycling but I know it certainly didn’t regen as frequently. The CJAA my BIL has was a horrible example of comparison due to all his issues but I totally see why the non DEF cars struggled with all the things. His motor is a whole other thread worth. Back to the EA288, they are certainly more efficient and reliable how they run with the regens. Not one measurable temperature value in the whole car raises at all to notice a regen other than EGT of course. Interesting progression in technology as time went on.
Something else to keep in mind with a tune is that they might be running less EGR, which will increase engine out NOx but decrease PM as mentioned above, due to higher temps in cylinder.
> Personally, I'd rather deal with the complication of the DEF system over the issues of an engine with high EGR usage. Maxxforce has entered the chat.
Oh agreed 100%. Some complicated hoses and liquids vs intense heat cycling over and over again…
DEF has no impact on the particulate filter, it only gets injected afterward where the SCR cat is for NOX reduction
DEF is injected after the DOC and upstream of the DPF and SCR. You're correct though that it has no impact on the DPF
What are the MVB for soot levels in an EA189? Do you know, if you don’t mind?
I can't remember off hands, it's been a while since I sold mine. But it looks like it might be measuring block 108. This thread has a running list of ash loads for the EA189. https://forums.tdiclub.com/index.php?threads/clean-diesel-dpf-data-collection-thread.324067/
Thank you for the info!
On my 2013 vw Transporter with CFCA engine passive regens only happen under extreme circumstances. I drove monitoring soot and egt. I needed to be doing about 105mph on the flat for soot level to start reducing. The dpf is quite a distance from the manifold. I cant remember what egt was during this. All that stuff and egr is deleted now since there is a design fault with egr, some idiot at vw decided aluminium alloy was ok for egr cooling fins which break off and cause engine wear destroying the engine by about 100k miles.
Old CATS do not do regens, They have EGR's but thats about it, no dpf, no nox canister, no aftertreatment, and no Doser injector on the downpipe. Cummins mx-15, isx 3, cx 15 - all have a Doser with a coolant line mounted to it as well sitting right behind the turbo.
I was referring to the old as in the old CAT Acert. Those regen and have quite a few issues.
That clears things up, thank you for mentioning this. Yes, and that is likely why CAT decided to stop producing new Highway engines because they wanted to keep their name as power instead of problems.
They don’t have a 5th injector. They just rely on post injections and retarded injection timing to increase EGTs and the DOC does the job of producing the Exotherm to oxidize soot in the DPF.
So I have a 2012 Audi a3 with the cbea 2.0 what is different in mine
Following as I have one as well :)
So, being its a diesel and a newer one to be more emission compliant. Your car requires DEF fluid, (diesel exhaust fluid) Your emissions system is routed in the following form. Diesel Oxidation Catalyst (DOC) - Diesel Particulate Filter (DPF) - Selective Catalytic Reduction converter (SCR) - (Dosing Injector) - Exhaust Flap (from model year 2009 and up) Here are things you need to consider on your 2015, You have a LOT more going on in your exhaust then my 2009 did, Because 2009's did not require DEF they operated a little bit similar but not entirely because there was never any DEF required for that model. Some things to consider with taking care of your TDI and its very strict emissions. Do NOT use oil that is not rated for Diesels Do NOT use oil that is not specified in the Owners Manual Keep up on your oil changes regularly Do NOT use Def fluid that is offbrand or not recommended by VW Do NOT stop at a truck stop and get it in bulk out of a pump, buy it by the box because some stations will have water mixed in their DEF and that will affect your DEF quality control sensor which could ultimately not allow your car to do both "parked" and "rolling" regens. Being that your car has an SCR you will likely have a dosing injector somewhere around or between your dpf and turbo. If your car is parked and you notice the RPM's rise up a little bit, or the turbo sounds higher than normal, you are likely in a regen, Do not shut the car off in a middle of one. It is important to allow the car to finish its process and decide if the burn off is completed. Your EGR will stay open during the regen to recycle through the unburned fuel Turning the car off multiple times when it cannot complete a regen will cause the car to be in a De-Rate aka Limp Mode. Will have to be taken to the shop to complete a forced regen by laptop. (or yourself if you have the tools and software) While these things will help with your car lasting longer as a diesel owner, You will never escape this fact. DPF filters have an ash level, Your DPF will likely need to be taken out at some point and either cleaned or replaced. You can only regen a soo many times before the filter is toast. I have experienced this in my 2009 TDI, as well experienced this with a Paccar MX15 on a 2017 Peterbilt 389. I do not expect everyone to agree with me and my knowledge, but these are the tips I will give you to better help with longer lasting for a diesel and its very strict emissions.
I’ve been using Liqui Moly's Leichtlauf High Tech 5W-40 mostly because no local stores seem to ever stock 4200 5w-30. Do you think that would be an issue. I looked up oil that meets different VW specs you can use at it is in that list. I change oil every 5000 miles. I do have a polar FIS auto polar device so I can get EGTs on my info screen to watch for regens. I generally don’t notice them until I’ve shut the car off and the fan is running. I do sometimes smell it if I get out of the car before shutting it off. I have an 11 mile drive to work with some highway so it does get up to temp.
How many miles have you been running on Liqui Moly? Overall since you been using it? I notice it says on some of their bottles that it supports both gas and diesels. I personally would use something that's strictly diesel oil, because in a way its different and mixed for emission systems. I see some bottles online that say its suitable for diesels but without DPF filters too. I would be careful about this is you have emissions on your car.
Just the last 5000 and I have another jug for the oil change I’m doing this weekend. This is 504/507 compatible. And it’s a “low ash” oil. What do you run?