Diesel Particulate Filter Gauge , Is It Working

[AH64ID]

Hopeful…I have a lot to do in 4 weeks before the 6,000+ mile trip

I did notice the truck had 3 hours do idle time on it when I picked it up with 15 miles on it. Maybe that’s why I’m already at 30%?

I picked my 22 up last Friday and the gauge was at 25%, lots of cold idle time in/around the dealership. 2 of the 4 hours were idle at delivery. 150 miles later the gauge is at 0% thanks to passive regen.

Very likely the idle is what caused it, but it burns out quick once you're driving at highway speeds or towing/hauling.

~6,500 miles driven, no regens so far. After about 45 minutes of highway driving unladen or ~30 minutes of towing my DPF guage goes back to 0.

You have had plenty of regens, you just haven't noticed them. The engine will regen every 24 hours of runtime regardless of DPF soot level.

 

[Leadchuncker]

which is after the DPF the SCR… it goes DOC DPF then SCR i have it all laid out on my shed floor i could send you a picture if you like… i had 53k when i removed it and always used the cheapest DEF i could find and the DPF still looks pretty clean all considering and the SCR is spotless as it should be


View attachment 43385

Let me ask you this. Is it the same setup as a cc truck? A ford differs from a 250/350 to a 450/550. The 450/550 is downstream of everything instead of upstream.
My opinion of it is def is a complete foul up. I’ll use the 350 in the shop. It somehow started pushing oil through the turbo which has gummed up everything in front of the turbo. It’s like black mud. It’s the same deal with spraying Def into the exhaust, the moist water vapor is trapping particles and making them stick to everything and that’s how the clogging up starts.

Back to the dpf and scr. Is this a timed event when it regins, does it sense when it needs to regin or both ?
When your watching the gauge and it shows let’s say 50% is that reading the dpf, the scr, or both ?

 

[AH64ID]

Back to the dpf and scr. Is this a timed event when it regins, does it sense when it needs to regin or both ?

Both. Every 24 hours of run time and if the DPF needs it.

I started taking note of regens on my 2018 around 243 hours and 9000 miles. Since then I have only had regens at the 24 hour mark and never because the DPF was plugged.

The 24 hour clock starts at the end of a regen so it's slowing rolling forward, hence the 243 hours at the regen when I started tracking them. Based on the way the hour meter works I have seen it happen at 23 and 25 hours but that just a function of the hour meter, the regen is still happening 24 hours after the last completion.

I also noted that a stationary regen (alfa OBD) would restart the 24 hour clock, as did a ECM software upgrade (went well over 24 hours on that regen interval).

When your watching the gauge and it shows let’s say 50% is that reading the dpf, the scr, or both ?

DPF. The SCR doesn't trap anything and isn't part of the regen process.

 

[H3LZSN1P3R]

Let me ask you this. Is it the same setup as a cc truck? A ford differs from a 250/350 to a 450/550. The 450/550 is downstream of everything instead of upstream.
My opinion of it is def is a complete foul up. I’ll use the 350 in the shop. It somehow started pushing oil through the turbo which has gummed up everything in front of the turbo. It’s like black mud. It’s the same deal with spraying Def into the exhaust, the moist water vapor is trapping particles and making them stick to everything and that’s how the clogging up starts.

i have never seen any scr system before the DPF that would defeat the purpose as the dpf is what raises the exhaust temps the most and DEF is only there to cool the exhaust fumes… all the fords are the same orientation just different piping on the C&C

If there is oil on the pressure side of a turbo its usually from the Crank case vent puking oil to the non pressure side through the filter then going through the turbo but can be a bad turbo oil seal but usually you find a bad turbo oil seal when the engine does a runaway lol…

Def wont clog anything up as it NEVER is sprayed before a filter…

DEF is DEF there is no one better than another due to what it does. Its just cooling the exhaust fumes

 

[H3LZSN1P3R]

Back to the dpf and scr. Is this a timed event when it regins, does it sense when it needs to regin or both ?
When your watching the gauge and it shows let’s say 50% is that reading the dpf, the scr, or both ?

Both for regen intervals either 24hrs or DPF soot level


The SCR is not a filter and can no way get clogged so the gauge is the DPF only

 

[superjoe83]

i have never seen any scr system before the DPF that would defeat the purpose as the dpf is what raises the exhaust temps the most and DEF is only there to cool the exhaust fumes… all the fords are the same orientation just different piping on the C&C

If there is oil on the pressure side of a turbo its usually from the Crank case vent puking oil to the non pressure side through the filter then going through the turbo but can be a bad turbo oil seal but usually you find a bad turbo oil seal when the engine does a runaway lol…

Def wont clog anything up as it NEVER is sprayed before a filter…

DEF is DEF there is no one better than another due to what it does. Its just cooling the exhaust fumes

The F-250-350's do have the scr before the dpf, the doc is what actually raises the temp for regens, it is located before the scr on fords systems, you can see that the def doser is right after the doc on the picture, the dpf is the last thing on fords setup, the ford c&c do have the same arrangement as the Rams (doc/dpf/scr)

 

[Jimmy07]

DEF is DEF there is no one better than another due to what it does. Its just cooling the exhaust fumes

The purpose of DEF isn’t to cool the exhaust fumes. It’s sole purpose is to create the chemical reaction with nox to lower it’s concentration by converting it to nitrogen and water.

 

[H3LZSN1P3R]

The purpose of DEF isn’t to cool the exhaust fumes. It’s sole purpose is to create the chemical reaction with nox to lower it’s concentration by converting it to nitrogen and water.

Never actually looked in to it that deep it was always explained to me as it cools the exhaust tempture below the threshold where nOX is created

 

[H3LZSN1P3R]

The F-250-350's do have the scr before the dpf, the doc is what actually raises the temp for regens, it is located before the scr on fords systems, you can see that the def doser is right after the doc on the picture, the dpf is the last thing on fords setup, the ford c&c do have the same arrangement as the Rams (doc/dpf/scr)

View attachment 43401

I have only deleted the Cab and chassis before…. Perhaps this is why i see more deleted fords than any other due to the silly design… i have a 15 f350 here that may be getting a weight loss kit so ill get to see that silly setup first hand

 

[AH64ID]

Never actually looked in to it that deep it was always explained to me as it cools the exhaust tempture below the threshold where nOX is created

nOX is created in the cylinder during combustion.

EGR drops the cylinder temps to reduce nOX, and when EGR isn’t as active (higher engine load) then DEF/SCR cleans it up.

EGR use is inverse to DEF use, which is why I get 1000 mpg on DEF empty and 500 mpg DEF towing.

 

[Leadchuncker]

Both. Every 24 hours of run time and if the DPF needs it.

I started taking note of regens on my 2018 around 243 hours and 9000 miles. Since then I have only had regens at the 24 hour mark and never because the DPF was plugged.

The 24 hour clock starts at the end of a regen so it's slowing rolling forward, hence the 243 hours at the regen when I started tracking them. Based on the way the hour meter works I have seen it happen at 23 and 25 hours but that just a function of the hour meter, the regen is still happening 24 hours after the last completion.

I also noted that a stationary regen (alfa OBD) would restart the 24 hour clock, as did a ECM software upgrade (went well over 24 hours on that regen interval).



DPF. The SCR doesn't trap anything and isn't part of the regen process.

I kinda thought the scr had some kind of honeycomb filter/baffle that was the last device to help clean things up after burning out the dpf and it would build up with deposits. I guess I’m wrong on thinking that so what does the scr do ?

 

[AH64ID]

I kinda thought the scr had some kind of honeycomb filter/baffle that was the last device to help clean things up after burning out the dpf and it would build up with deposits. I guess I’m wrong on thinking that so what does the scr do ?

The SCR uses DEF to convert nOX to Nitrogen and Carbon Dioxide.

 

[Leadchuncker]

The SCR uses DEF to convert nOX to Nitrogen and Carbon Dioxide.

By that it has to build up deposits and can plug up ?

 

[AH64ID]

By that it has to build up deposits and can plug up ?

Why would it have to?

Like everything there is going to be a useful life.

 

[Leadchuncker]

Why would it have to?

Like everything there is going to be a useful life.

Maybe I’m over thinking it.. A mist introduced to burned particles in a tube and chamber I just think it would cause buildup over time. I guess it’s so hot and the force of the exhaust blowing it doesn’t have a chance

 

[AH64ID]

Maybe I’m over thinking it.. A mist introduced to burned particles in a tube and chamber I just think it would cause buildup over time. I guess it’s so hot and the force of the exhaust blowing it doesn’t have a chance

No particles, just gasses. The DPF is before the SCR and keeps all the particles in it, which is why the tailpipe stays so clean.

 

[Leadchuncker]

No particles, just gasses. The DPF is before the SCR and keeps all the particles in it, which is why the tailpipe stays so clean.

Thanks..
I just see so many complaining that their def gauge sets at 100% and get the go to dealer message. Just trying to understand why that happens it seems frequently.

 

[Leadchuncker]

No particles, just gasses. The DPF is before the SCR and keeps all the particles in it, which is why the tailpipe stays so clean.

it’s just like my friends 21. His would show a regen a few times a day, his gauge would show it at over 50% one day, few days later it’d be at 100 and the go to dealer message. The dealer looked at it 3 times, clean whatever, clear the codes and within a few days it was doing the same thing. After swapping the def fluid out and adding a fuel additive everything cleared up.
If def fluid isn’t a factor why after changing correct the problem? I don’t see the fuel additive helping with that but I could be wrong.

 

[Jimmy07]

Thanks..
I just see so many complaining that their def gauge sets at 100% and get the go to dealer message. Just trying to understand why that happens it seems frequently.

Probably because you are calling it a DEF gauge instead of the DPF gauge that everyone else in this thread is referring to?

 

[Leadchuncker]

Probably because you are calling it a DEF gauge instead of the DPF gauge that everyone else in this thread is referring to?

My mistake on that