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Discussion Starter · #1 ·
I bought my 2018 F150 PS Diesel used at 18k miles. Very shortly after that it started over heating. The issue was traced back to a recall repair that was done poorly and led to the replacement of both turbos and my dealership having my truck for about 8 weeks. This was before I took possession. Since then all was well, regular maintenance and was well cared for. Check engine light let to a code requiring a new DPF, and current one is “cracked”. This will cost over $3K and is not considered under power train. Can anyone guide me to any possible connection to the original issue and this one. I can’t afford that and common sense says it’s related OR it’s a manufacturer defect. Any guidance is appreciated. - Stacey
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@SSBL - let me be the first to welcome you to the forums, although I would have preferred it be on a better note...

Any idea what you Vehicle manufacture date is? You "might" luck out with your 3yr/36K Bumper-to-Bumper Warranty.

You are well below the 36K part of the 3yr/36K Bumper-to-Bumper Warranty, but probably very close to the 3 years:
  • 2018 F150 PSDs (Power Stroke Diesels) were very late 2018 Model Year
  • Earliest delivery we saw here are the forums was June 2018
  • My 2018 Platinum was factory-ordered at end of Jan 2018 & I didn't take delivery until 09/22/18
    • With 34.5K on the odometer, my 3yr/36K B-to-B warranty will expire in 10 days!
Diesel Particulate Filter won't be covered by Powertrain Warranty but rather by Emissions Warranty:
  • Our vehicles are less than 8500 lbs so are classified in the Car and Light Truck category
  • Therefore All Emissions parts have a 2yr/24K Emissions Warranty
    • If you are lucky to be in California, all parts are covered 7yr/70K
    • All parts covered are listed on Page 20 of the Warranty Guide (attached below)
  • "Certain" vehicle Emissions parts have 8yr/80K Emissions Warranty:
    • Catalytic converters
    • Electronic emissions control unit
    • Onboard emissions diagnostic devices
    • Battery Energy Control Module (BECM)
I can't see how/why the DPF shouldn't be listed as one othe "Certain" parts, but it isn't. Not really sure I like this (I think we are getting screwed as the bigger PowerStrokes carry 5yr/50K on all Emission parts) but this is how I read the Warranty Guide.

My Plan of Attack would be:
  1. Play stupid and tell them this is covered by Emissions Warranty and the DPF is listed on Page 20
  2. If they push back that Page 20 parts are only 2yr/24K warranty, then ask for an OASIS report for your VIN
  3. Cross-your-fingers that your truck is < 3 years old and covered by 3yr/36K Bumper-to-Bumper
    => Pages 18/19 clearly state 3yr/36K B-to-B exceeds the federally mandated 2yr/24K Emissions
    => Warranty starts on date vehicle was sold and not manufactured
    => Hopefully with your very low mileage, yours was a 2018 leftover that wasn't sold until 2019
  4. Purchase a Flood ESP online and don't disclose your current dilemma
This is yet another reason as to why I purchased an Extended Warranty ESP from Ford.

I would hope given this truck's history with your dealership that they wouldn't screw you over and try to make things right, as I would be pissed if I bought a used truck from a Ford dealer and the DPF grenaded at 18K miles = something went wrong and they knew this truck was a problem child. Maybe a discussion with the Sales Manager and GM is warranted? I wouldn't back down... Up to GM + Sales Manager + Service Manager + Parts Manager to act as a team to make things right on this used "low mileage" vehicle their dealership sold you.

Good luck and please let us know how you make out!

Excerpts from 2018 F150 Warranty Guide
(Page 17)
Font Parallel Number Document Screenshot

(Page 18)
Font Screenshot Paper Document Parallel

(Page 19)
Font Document Parallel Number Letter

(Page 20)
Font Screenshot Number Document Parallel
 

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The issue was traced back to a recall repair that was done poorly and led to the replacement of both turbos
I suspect something is very wrong with the place that did your service. They can't replace BOTH turbos since the truck only came with only one turbo, yes only 1 not 2. Try a different dealership and never come back to the same place.


I assume that you're in USA, Ford covers the emissions for 8 years/80k and DPF is one of the items that is covered under emissions.

When service guys slap you with a powertrain rate quote for emissions work; time to change. Not sure if it was the same place that did the recall but going to different place would by my

If you're out of warranty, you might find a shop to just delete the DPF and never have to worry about emissions.
 

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Ford covers the emissions for 8 years/80k and DPF is one of the items that is covered under emissions.
@Stroki - that was what I initially thought also until I dug into the 2018 F150 Warranty Guide....

On Page 18, note that only "certain" parts are covered by 8yr/80K Emissions Defect warranty:
  • Catalytic converters
  • Electronic emissions control unit
  • Onboard emissions diagnostic devices
  • Battery Energy Control Module (BECM)
and everything else (Parts listed on Page 20 above) is 2yr/24K:
Font Number Document Circle Rectangle

but clearly notes Ford's 3yr/36K Bumper-to-Bumper surpasses this mandatory federal coverage.
 

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Discussion Starter · #5 ·
I suspect something is very wrong with the place that did your service. They can't replace BOTH turbos since the truck only came with only one turbo, yes only 1 not 2. Try a different dealership and never come back to the same place.


I assume that you're in USA, Ford covers the emissions for 8 years/80k and DPF is one of the items that is covered under emissions.

When service guys slap you with a powertrain rate quote for emissions work; time to change. Not sure if it was the same place that did the recall but going to different place would by my

If you're out of warranty, you might find a shop to just delete the DPF and never have to worry about emissions.
I should have stated the turbo was replaced twice. I misread the report. I have some questions but first thank you so much for the information. Service manager is dodging me, surprise!

Other information:

Truck was not purchased at this dealership and sold as is. I had a mechanic friend inspect it and drive it several times. I opened it up on the highway 3 times and also took it home first. Tough to believe a brand new diesel truck would have catastrophic issues. I also was relying on warranty which up until now has covered all repairs. But here we are.

1. Will the OASIS report have both sale and manufactured date on it? Will it have all the previous issues from former owner?
2. Assuming that the 3/36 is rated by what comes last because I have 50k on it.
3. I’m in South Texas, no CA advantage.
4. Showing up unannounced this pm or tomorrow am, where do I start?
5. Part is ordered, should I walk away or keep fighting.
6. They said it is drivable but will start to lose power. Drive it and get coverage?
6. I’m a retired teacher so I have the time and motivation to be a huge nuisance. Also know the owners but I’m really trying not to be that person.
Again, thanks!
 

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Discussion Starter · #6 ·
@SSBL - let me be the first to welcome you to the forums, although I would have preferred it be on a better note...

Any idea what you Vehicle manufacture date is? You "might" luck out with your 3yr/36K Bumper-to-Bumper Warranty.

You are well below the 36K part of the 3yr/36K Bumper-to-Bumper Warranty, but probably very close to the 3 years:
  • 2018 F150 PSDs (Power Stroke Diesels) were very late 2018 Model Year
  • Earliest delivery we saw here are the forums was June 2018
  • My 2018 Platinum was factory-ordered at end of Jan 2018 & I didn't take delivery until 09/22/18
    • With 34.5K on the odometer, my 3yr/36K B-to-B warranty will expire in 10 days!
Diesel Particulate Filter won't be covered by Powertrain Warranty but rather by Emissions Warranty:
  • Our vehicles are less than 8500 lbs so are classified in the Car and Light Truck category
  • Therefore All Emissions parts have a 2yr/24K Emissions Warranty
    • If you are lucky to be in California, all parts are covered 7yr/70K
    • All parts covered are listed on Page 20 of the Warranty Guide (attached below)
  • "Certain" vehicle Emissions parts have 8yr/80K Emissions Warranty:
    • Catalytic converters
    • Electronic emissions control unit
    • Onboard emissions diagnostic devices
    • Battery Energy Control Module (BECM)
I can't see how/why the DPF shouldn't be listed as one othe "Certain" parts, but it isn't. Not really sure I like this (I think we are getting screwed as the bigger PowerStrokes carry 5yr/50K on all Emission parts) but this is how I read the Warranty Guide.

My Plan of Attack would be:
  1. Play stupid and tell them this is covered by Emissions Warranty and the DPF is listed on Page 20
  2. If they push back that Page 20 parts are only 2yr/24K warranty, then ask for an OASIS report for your VIN
  3. Cross-your-fingers that your truck is < 3 years old and covered by 3yr/36K Bumper-to-Bumper
    => Pages 18/19 clearly state 3yr/36K B-to-B exceeds the federally mandated 2yr/24K Emissions
    => Warranty starts on date vehicle was sold and not manufactured
    => Hopefully with your very low mileage, yours was a 2018 leftover that wasn't sold until 2019
  4. Purchase a Flood ESP online and don't disclose your current dilemma
This is yet another reason as to why I purchased an Extended Warranty ESP from Ford.

I would hope given this truck's history with your dealership that they wouldn't screw you over and try to make things right, as I would be pissed if I bought a used truck from a Ford dealer and the DPF grenaded at 18K miles = something went wrong and they knew this truck was a problem child. Maybe a discussion with the Sales Manager and GM is warranted? I wouldn't back down... Up to GM + Sales Manager + Service Manager + Parts Manager to act as a team to make things right on this used "low mileage" vehicle their dealership sold you.

Good luck and please let us know how you make out!

Excerpts from 2018 F150 Warranty Guide
(Page 17)
View attachment 2389
(Page 18)
View attachment 2390
(Page 19)
View attachment 2391
(Page 20)
View attachment 2392
Just saw this plan of action, thank you. Will get back to you. Thanks again. - Stacey
 

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@SSBL - thanks for filling in missing and since purchase details, as it helps fll in some blanks.

1a. Will the OASIS report have both sale and manufactured date on it?
It will have the date it was sold/entered into service
Manufacture date might only be on window sticker & Driver's side door pillar
1b. Will it have all the previous issues from former owner?
Yes, any recall work performed by any Ford Dealer will be documented in VIN-specifc OASIS report
2. Assuming that the 3/36 is rated by what comes last because I have 50k on it.
If you are over 50K now, then you've exceeded mileage part of the 3yr/36k (which ever comes first)
=> You only mentioned mileage when your purchased (18K) in your original post

With this new info, I don't think you have any cards to play with existing Ford Warranty coverages, but I'd still have a conversation with the Sales manager to see if they can discount parts or service unless they are being firm on "as-is" sale.
 

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@Stroki - that was what I initially thought also until I dug into the 2018 F150 Warranty Guide....

On Page 18, note that only "certain" parts are covered by 8yr/80K Emissions Defect warranty:
  • Catalytic converters
  • Electronic emissions control unit
  • Onboard emissions diagnostic devices
  • Battery Energy Control Module (BECM)
and everything else (Parts listed on Page 20 above) is 2yr/24K:
View attachment 2393
but clearly notes Ford's 3yr/36K Bumper-to-Bumper surpasses this mandatory federal coverage.
Thanks for correction. I was under assumption that emissions goes past 3/36 so from booklet 8/80 looked about right. Friend of mine had his SD DPF warranted past 70k but I'm not sure who warrantied.
 

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SSBL,

Ouch, feel your pain from the service you got.

I concur jmperlik points

Since you are out of warranty. You can try getting local shop welding the crack, depending on the crack it might be possible..

I personally think you can find a shop to delete the DPF and save $1,000. With deleted DPF, never have to worry about adding DEF fluid or any other emission related problems and get more power and gas millage. Not sure if now Texas is doing tests for diesel emissions or not.
 

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Discussion Starter · #10 ·
SSBL,

Ouch, feel your pain from the service you got.

I concur jmperlik points

Since you are out of warranty. You can try getting local shop welding the crack, depending on the crack it might be possible..

I personally think you can find a shop to delete the DPF and save $1,000. With deleted DPF, never have to worry about adding DEF fluid or any other emission related problems and get more power and gas millage. Not sure if now Texas is doing tests for diesel emissions or not.
I’m sorry. I don’t understand. “Delete” DPF? Like have it removed from service record or from the vehicle? Or both, lol. I thought DEF was necessary for the engine? It’s just an emissions issue? I need to understand more. TIA.
 

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I’m sorry. I don’t understand. “Delete” DPF? Like have it removed from service record or from the vehicle? Or both, lol. I thought DEF was necessary for the engine? It’s just an emissions issue? I need to understand more. TIA.
Basically, remove from vehicle/operation completely by punching a hole thru it (filter) or replacing it with new hollow pipe in its place; it does require programming in order for engine to run properly.

DPF is Diesel Particulate Filter; deleting the "filter" part, everything else can stay in place. Other way of explaining is that the "filter assembly - aka DPF" can stay in place but the inside guts get to be removed.

If you just remove DPF without programing new software then truck isn't going to run. If you just program and keep program DPF in place truck is going to very slowly loose power until DPF fills up with sod(dust particles) and then completely stops once it's plugged up, depends on driving habit anywhere 5K -50k before getting plugged up.

If you are going to run over 60 horsepower tune than your truck will puff black smoke during acceleration that you might have noticed on the tractor trailers.

In order for DPF to be cleaned up from sod in the filter during the normal operation; vehicles go into "regenerative mode" and burn up the sod. Burning up the sod is done by putting fuel in the exhaust and cranking up the heat on the exhaust; the heat travels thru turbo before it gets to DPF. It heats up to the point that heat can melt the turbo during regeneration. Regeneration puts extra heat stress on the engine.

When deleted, no regeneration is needed and engine isn't cooking or looking at exhaust any longer.

DPF is purely emissions thing nothing to do with engine performance.
 

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Discussion Starter · #12 ·
Update

After many phone calls and a stint of just sitting in the service managers office until he returned, I’ve got it down to $607 and a free replaced tire. I feel like I still have a lot of “Karen” left in me but I actually need my truck at the ranch this week. My last question is what next? Do I need/is it worth it to get an extended warranty on this vehicle? If so how? Recommendations? I feel like this might be karma for all the “we’d like to talk to you about your extended warranty” jokes I’ve made on social media. Appreciate advice so far, this is a great group. - Stacey
 

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In order for DPF to be cleaned up from sod in the filter during the normal operation; vehicles go into "regenerative mode" and burn up the sod. Burning up the sod is done by putting fuel in the exhaust and cranking up the heat on the exhaust; the heat travels thru turbo before it gets to DPF. It heats up to the point that heat can melt the turbo during regeneration. Regeneration puts extra heat stress on the engine.
I would just like to clairify the common mis-conception that a regen causes extra heat to travel through the turbo. All the regen does is injects some fuel into the cylinder during the exhaust stroke, which pushes the aerosolized fuel into the exhaust. No extra heat/combustion occurs in the engine itself, and thus the turbo is not exposed to any additional heat as a result of this.

The additional heat is created in the DPF itself, in our case it's impregnated with a precious metal catalyst, and when the hydrocarbons (diesel fuel) hits this, it is oxidized there (burns) to create the heat that cleans out the DPF. Other DPF systems like that in the 6.7 use a separate diesel oxidation catalyst (DOC) which is upstream of the DPF that creates the heat there, but again, downstream of the turbo.
 

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I would just like to clairify the common mis-conception that a regen causes extra heat to travel through the turbo. All the regen does is injects some fuel into the cylinder during the exhaust stroke, which pushes the aerosolized fuel into the exhaust. No extra heat/combustion occurs in the engine itself, and thus the turbo is not exposed to any additional heat as a result of this.

The additional heat is created in the DPF itself, in our case it's impregnated with a precious metal catalyst, and when the hydrocarbons (diesel fuel) hits this, it is oxidized there (burns) to create the heat that cleans out the DPF. Other DPF systems like that in the 6.7 use a separate diesel oxidation catalyst (DOC) which is upstream of the DPF that creates the heat there, but again, downstream of the turbo.
I strongly disagree with what you've said here. The additional heat created during exhaust regen is made in the cylinders when the extra fuel is injected during the exhaust stroke. The extra fuel then burns, further raising the exhaust temperature. This extra heat is then carried downstream to the DPF, directly through the turbo's exhaust turbine. Without a diesel oxidation catalyst like the Super Duty, this is the only place in the exhaust stream extra heat is created, not absorbed.

If you believe otherwise, then please explain why the EGT- which I monitor using the EGR inlet temperature sensor (upstream of the turbo)- goes UP ~200-300F when the truck is performing a DPF regen.
 

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I strongly disagree with what you've said here. The additional heat created during exhaust regen is made in the cylinders when the extra fuel is injected during the exhaust stroke. The extra fuel then burns, further raising the exhaust temperature. This extra heat is then carried downstream to the DPF, directly through the turbo's exhaust turbine. Without a diesel oxidation catalyst like the Super Duty, this is the only place in the exhaust stream extra heat is created, not absorbed.

If you believe otherwise, then please explain why the EGT- which I monitor using the EGR inlet temperature sensor (upstream of the turbo)- goes UP ~200-300F when the truck is performing a DPF regen.
You just proved my point. If you inject fuel on the exhaust stroke... you're at very low pressure as the exhaust valves are open. If you recall how a diesel engine works, there is no ignition without compression. so if you inject diesel at nearly atmospheric pressure, it's not going to burn, it gets pushed through into the exhaust (the heat of the engine and the fine injectors ensure that it's mostly a vapour at that point). The point of this is to provide hydrocarbons to the DOC or catalyst where the fuel can oxidize and create heat. You can see this if you monitor the PID's during your regen. your EGT at the turbo or before is 200-300 degrees less than behind the DPF. In the case of our engines, the catalyst is impregnated into the DPF substrate, this is a newer way of doing it and provides more heat directly to the DPF/soot with less fuel required.

Now, the EGTs will increase a bit as you mentioned, and the reason is simply that the catalytic reaction in the DPF will start and react more efficiently in higher temperatures (the reason some manufacturers are moving the DPF closer to the engine), so the engine does raise EGTs a couple hundred degrees. In this case, the higher EGT simply comes from reducing EGR, and therefor increasing the amount of available oxygen for combustion (not by adding more fuel). In doing this, the exhaust then also has more excess O2 in the stream which is required for the catalytic reaction in the DPF to occur. The EGTs are not raised to any dangerous level, and would be similar to what they would be anyways if you were running deleted (yes). The whole point of EGR is to reduce combustion temps, so by reducing the amount of non-combustible exhaust that gets recirculated, will raise EGTs.

Now, since combustion temps are increased, DEF injection increases accordingly to counteract the additional NOx formation during the process. that is why you can hear the DEF injector clicking away during a regen.

9 people out of 10 making statements on youtube don't actually understand the process, and they are usually trying to sell you products by playing on your fear that this will somehow destroy your engine. Keep that in mind.
 

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I've been lurking on this forum while researching issues on F-150 diesels in preparation for a potential purchase. Just when you think you know everything, something new comes along. In this case, that a DPF is considered a consumable and is only required to be covered for 24,000 miles as far as EPA is concerned. If you read the EPA regulations, only catalytic converters are covered to 80,000 miles. It may not stand up in court, but since this vehicle does away with the DOC and instead puts catalyst in the substrate of the DPF, as Laytunes states (and I concur), isn't the DPF indeed a catalytic converter?

Bringing it back to the original question "should I buy an extended warranty, given the failure?" I would personally say yes. This is coming from a person who has never purchased an extended warranty. My feeling is that DPFs do not fail (they will eventually foul over several hundred thousand miles) unless something upstream of the filter is wrong. It could be wrong motor oil, a failed turbo dumping a bunch of oil into the exhaust, excessive blow-by, failed injector, etc.....but the biggest issue with a DPF is that it hides the evidence of excessive soot or of oil in the exhaust until it destroys itself. Maybe your DPF failed because of some past one-time failure like the turbo, but I would be a bit concerned that the DPF is going to fail again....

I'll go back to hiding behind my rock for now, unless I end up buying one of these rigs.
 

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After many phone calls and a stint of just sitting in the service managers office until he returned, I’ve got it down to $607 and a free replaced tire. I feel like I still have a lot of “Karen” left in me but I actually need my truck at the ranch this week.
Stacey - congrats on getting the replacement DPF (and a tire!) for a much more reasonable price!

My last question is what next? Do I need/is it worth it to get an extended warranty on this vehicle? If so how? Recommendations? I feel like this might be karma for all the “we’d like to talk to you about your extended warranty” jokes I’ve made on social media.
If you read back thru previous posts on this topic, you'll find varying opinions and "camps" on ESPs (Extended Service Plans) or what are sometimes called "Extended Warranties" that can be purchased on top of your vehicle purchase.

Given my 2018 was the first model year for the 3.0L V6 Diesel, I did something I had never done before when purchasing a new vehicle = I purchased both extended warranty and extended maintenance plans for my F150 PSD

From some responses in the "Extended Warranty" threads in these forums, I can tell you that I'm definitely in the minority WRT extended warranties.

First let me explain what I purchased and then I will explain my reasoning behind this decision.

Ford ESPs are marketed under the "Ford Protect" brand:
My 2018 Platinum F150 PSD is my third F150 Platinum having owned a 2010 5.4L V8 and a 2015 5.0L V8 previously. For the 2010 and 2015 F150s, I balked at even entertaining the concept of an Extended Warranty, as I thought they were overpriced and unnecessary, and then Ford introduced the 2018 F150 PowerStroke Diesel.

While I had faith in the F150 chassis and loved the creature comforts of the F150 Platinum trim level, this was a new engine option for the F150 platform, although not a new/never-been-used-before engine as JLR used this V6 Lion engine in LandRover SUVs.

Stepping back and looking at everything "new" I was getting on my 2018 F150 PSD:
  • New 3.0L V6 Turbocharged Diesel engine
  • All of the EPA-mandated emission systems that come with modern-day diesel vehicles
    • DPF
    • SCR
    • DEF tank/system
  • Ton of new options:
    • Auto Start/Stop
    • Adaptive Cruise Control
    • Auto-Lane Keeping
    • Parking Assist
    • Trailer back-up Assist
    • etc
  • My beloved creature comforts:
    • 360 cameras
    • Power massaging front seats
    • Power-deployed running boards
    • etc
and wanting to own this F150 for longer than 5 years, I looked at what could possibly break after 3yr/36K Bumper-to-Bumper warranty and decided that it was time to look into an Extended Warranty.

With help from members on this forum, I found there are much cheaper ways (See Post #5 in Powerstroke Warranty thread) to get the same product (Ford Protect ESPs) than when you are sitting in the F&I Manager's office signing your financing paper work to purchase a vehicle. Those forum members in the other "camp" are 100% correct: The price for Ford ESPs are exorbitantly expensive while in the F&I office, but that is intentional because it is easier to tuck $20-$40/month extra to a monthly payment for an ESP when you are selling a vehicle for $60K-$70K.

Not only did I purchase an Extended Warranty for 8yr/100K if anything breaks on my truck, I also purchased an extended maintenance plan that in effect pre-pays for all service according to the documented maintenance schedule. My reasoning is that I didn't want anyone else but Ford to wrench on my truck, so that there can be no one else to blame for any service voiding any part of the extended warranty; i.e. if there is ANYTHING wrong with my truck, I drop it off at my dealer and it is their responsibility to fix.

I have seen big $$$ numbers that scare me in posts already for trucks less than 3 years old:
  • New engines
  • New ($7-$8K) and used ($3500) transmissions
  • Diesel Particulate Filters ($3000)
that make me feel better that I made the right decision. Add in the double EGR By-pass valve recalls and now our unicorn status due to Ford dropping this engine from the line-up, my decision is only further cemented.

Some may think this is crazy, but I call it "Peace of Mind" especially being a first model year of this new engine option.

Read up on the link I posted above for more details on Flood ESP who sells Ford protect plans online for prices closer to dealer cost than what is offered in the F&I office. I (and others) will tell you these prices are negotiable and I got both of my plans for roughly half of what it would have cost me during the F&I process = that is how much dealer markup there exists for tucking into a financing deal and why dealers love to add these in.

Please post back with your decision and what you went with if you do decide to go with an ESP.
 
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You just proved my point. If you inject fuel on the exhaust stroke... you're at very low pressure as the exhaust valves are open. If you recall how a diesel engine works, there is no ignition without compression. so if you inject diesel at nearly atmospheric pressure, it's not going to burn, it gets pushed through into the exhaust (the heat of the engine and the fine injectors ensure that it's mostly a vapour at that point). The point of this is to provide hydrocarbons to the DOC or catalyst where the fuel can oxidize and create heat. You can see this if you monitor the PID's during your regen. your EGT at the turbo or before is 200-300 degrees less than behind the DPF. In the case of our engines, the catalyst is impregnated into the DPF substrate, this is a newer way of doing it and provides more heat directly to the DPF/soot with less fuel required.

Now, the EGTs will increase a bit as you mentioned, and the reason is simply that the catalytic reaction in the DPF will start and react more efficiently in higher temperatures (the reason some manufacturers are moving the DPF closer to the engine), so the engine does raise EGTs a couple hundred degrees. In this case, the higher EGT simply comes from reducing EGR, and therefor increasing the amount of available oxygen for combustion (not by adding more fuel). In doing this, the exhaust then also has more excess O2 in the stream which is required for the catalytic reaction in the DPF to occur. The EGTs are not raised to any dangerous level, and would be similar to what they would be anyways if you were running deleted (yes). The whole point of EGR is to reduce combustion temps, so by reducing the amount of non-combustible exhaust that gets recirculated, will raise EGTs.

Now, since combustion temps are increased, DEF injection increases accordingly to counteract the additional NOx formation during the process. that is why you can hear the DEF injector clicking away during a regen.

9 people out of 10 making statements on youtube don't actually understand the process, and they are usually trying to sell you products by playing on your fear that this will somehow destroy your engine. Keep that in mind.


I see that you don't understand the basic concept of how diesel fuel can burn.

[ you're at very low pressure as the exhaust valves are open. If you recall how a diesel engine works, there is no ignition without compression. so if you inject diesel at nearly atmospheric pressure, it's not going to burn, ]

Don't confuse on how CI engine work with how diesel can burn. Have you ever released/spilled diesel on the ground and lit a match? Or played with flamethrower? There is no compression and you would be very surprised as diesel does burn. Yet, you do believe that diesel can burn without compression only in the DPF, somehow you don't apply that to the exhaust manifold.

Fact: Diesel can ignite below 100C
Fact: Diesel autoignition is below 225C
Fact: Diesel exhaust gas on exhaust stroke is around 600C
Fact: Diesel air/fuel ratio at idles is between 50:1 to 400:1
Fact: Diesel optimum fuel ratio is 14.5:1, where all the fuel is burned and no fuel and no oxygen is left. If the AFR is above 14.5:1 then there is oxygen left over.

On the exhaust stroke with exhaust valve open, exhaust gases leave combustion chamber at 600C while diesel fuel is injected, diesel vaporizes and there is still at least twice the amount of oxygen left than burned up in the combustion camber (using "rich" idle 45:1 AFR). Vaporized diesel ignites and continues to burn turbo. Other way of saying tossing more fuel into the fire.


The heat created by regeneration happens outside the combustion camber; away from the temperature sensors; and gas is very poor media for hear transfer. Same reason why it takes longer to notice overheated engine with blown radiator hose than broken water pump impeller. All the exhaust heat gets to be concentrated at the turbo. Turbo acts as a cooler for the exhaust. We would like to imagine the ideal " engine utopia" where everything runs perfect and sensors don't give any erroneous signals to the ecu, they never go bad and everything works like the manufacturer wished for; I got two front row tickets to circus with dozen unicorns and Greta Thunberg as their trainer.

navyR113 showed the reality, while you want to admit it or not. Scare tactics are guys who believe world is going to end in 10 years while their private jet makes more emissions then coal rollers. Emission controls provide unnecessary problems is a fact, just look at why this thread was started.
 

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I see that you don't understand the basic concept of how diesel fuel can burn.

[ you're at very low pressure as the exhaust valves are open. If you recall how a diesel engine works, there is no ignition without compression. so if you inject diesel at nearly atmospheric pressure, it's not going to burn, ]

Don't confuse on how CI engine work with how diesel can burn. Have you ever released/spilled diesel on the ground and lit a match? Or played with flamethrower? There is no compression and you would be very surprised as diesel does burn. Yet, you do believe that diesel can burn without compression only in the DPF, somehow you don't apply that to the exhaust manifold.

Fact: Diesel can ignite below 100C
Fact: Diesel autoignition is below 225C
Fact: Diesel exhaust gas on exhaust stroke is around 600C
Fact: Diesel air/fuel ratio at idles is between 50:1 to 400:1
Fact: Diesel optimum fuel ratio is 14.5:1, where all the fuel is burned and no fuel and no oxygen is left. If the AFR is above 14.5:1 then there is oxygen left over.

On the exhaust stroke with exhaust valve open, exhaust gases leave combustion chamber at 600C while diesel fuel is injected, diesel vaporizes and there is still at least twice the amount of oxygen left than burned up in the combustion camber (using "rich" idle 45:1 AFR). Vaporized diesel ignites and continues to burn turbo. Other way of saying tossing more fuel into the fire.


The heat created by regeneration happens outside the combustion camber; away from the temperature sensors; and gas is very poor media for hear transfer. Same reason why it takes longer to notice overheated engine with blown radiator hose than broken water pump impeller. All the exhaust heat gets to be concentrated at the turbo. Turbo acts as a cooler for the exhaust. We would like to imagine the ideal " engine utopia" where everything runs perfect and sensors don't give any erroneous signals to the ecu, they never go bad and everything works like the manufacturer wished for; I got two front row tickets to circus with dozen unicorns and Greta Thunberg as their trainer.

navyR113 showed the reality, while you want to admit it or not. Scare tactics are guys who believe world is going to end in 10 years while their private jet makes more emissions then coal rollers. Emission controls provide unnecessary problems is a fact, just look at why this thread was started.
Ok, well as an emissions scientist I can tell you that diesel injected in the cylinder on the exhaust stroke will not burn there. The whole point of introducing fuel there, or from a downstream injector, is to provide HC for the catalyzed oxidation process that takes place in the DOC. Yes there is O2 there, but not enough to sustain a flame, and certainly not enough to auto ignite the diesel (this is why EGR is used in the first place to control combustion in the cylinder, as that gas stream does not contribute to combustion! and therefor reduces cylinder temps). At the lower pressure, the O2 molecules are spread apart and not concentrated enough to auto-ignite the fuel, thats where your catalyst comes in. You also need to consider that the exhaust is moving very rapidly and is evacuated from the cylinder in nearly 1/10th of a second, and there's this thing called latent heat of vaporization which momentarily creates an exothermic reaction as the fuel droplets evaporate at the higher temps. This provides an ignition delay that is more than long enough for the exhaust to leave the manifold and turbo. The amount of fuel added on the exhaust stroke is also precision controlled at an amount that will not cause ignition. At no point is there an uncontrolled fire burning in your exhaust as many internet sleuths believe. If this were the case, your manifold and turbo would certainly fail very quickly.

You can watch this process unfold on your PIDs, the temps upstream of your turbo and DOC will be lower than after the DOC. That's just how it works, temp sensors are one of the easiest, most responsive, and robust sensors there are, they aren't lying to you. Yes your EGTs are increased slightly, but for the reasons mentioned before, and certainly not from combustion happening in your manifold and turbo.

Now this is how it works when everything is working as it should... of course there are plenty of situations that can cause things to run amuck that are well documented all over the internet that we won't get into. Yes the systems provide additional complexity to the engine, however I for one am happy to breathe clean air. You might not like science, but you can thank it for your air not looking like it does in china, and that your parents aren't dying 10 years too early due to poor air quality.
 
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