2018 Ford F-150 Powerstroke diesel King Ranch
Some updates, observations, and theories from me on this DPF Auto-regen topic:
My DPF Full % experiences observed over the last 3 weekends since being FORScan-enabled:
- I received my "new" used Lenovo Carbon X1 laptop about 2 weeks ago
- I purchased a Lifetime FORScan "full" license (I work in software also believe it is the right thing to do to support the developer anyway I can)
- I have implemented the FORScan mods documented in my signature
- I have implemented Operator Commanded Regeneration (OCR) FORSCAN mod but have yet to initiate a manual OCR
- I have been closely monitoring my DPF Full % and how my driving patterns affect it
After closely watching my DPF Full %, I seem to be requiring DPF regen far more often than the 325 mile range @kdjasper has reported earlier (don't have a good explanation for this...)
- Two weekends ago after doing some shopping, I was at 90% DPF full and about 5 miles from the closest Interstate. By the time I got to the interstate, I was at 100% full and watched it drop down in the 5% increments until it got to 0%. I drove a little too far before turning around so I climbed back up to 20% before getting home.
- Last weekend ago after a car wash, I noticed I was at 85% full, so I figured I'd try the same trip to "blow things out" again. I only got up to 90% Full before getting on the Interstate and I drove 30 miles without every making it 100% DPF full, so I never started a DPF regen. Stopped for dinner and drove 30 miles back and never hit 100% Full, so no regen again? Is this what "passive" (operating at high enough temperature that active regen not required) regen is?
- Two days later on my 15 minute 1-way commute into work, I noticed I started a regen about halfway thru my commute and only got down to only 70% by the time I got to work, where I turned my truck off and opened the door to hear the DPF ticking as I walked away.
- Again last week after a car wash, I was at 90% so figured I'd try my "blowout route" one more time. I jumped from 95% Full to DPF Full message (no %) just as I was getting onto the Interstate. I went thru a normal decrementing 5% regen over 20 miles/minutes and turned around to head home (didn't go as far as I did the first time above)
My Personal DPF Full % "Rules-Of-Thumb" developed over the past 4 weeks:
Based on all of the above, here are my theories on pontential side effects of these "Partial" DPF regens could be:
- Without enabling DPF % Full via FORSCAN, owners have no idea what is going on/when you need to regen
- DPF Auto-regen will not start unless you are very near to or at 100% Full or on DPF Full screen (I haven't seen any start earlier than 100% as @kdjasper has)
- You will start a regen if you are at DPF Full and reach the necessary operating temperatures but regen will stop pre-maturely (this is a "Partial" regen) if these conditions change
- If you never complete a full regen cycle (all the way down to 0% Full), you will be in a Partial DPF regen "death spiral" = more frequent regens due to hittign 100% DPF Full
My guess is that @kdjasper 's weekly 37 mile 1-way trip on Monday nights is providing the perfect therapeutic duty cycle for his DPF, hence why he's tracking to a 10K oil change interval.
- I think what was happening before I was FORScan-enabled, I was never making it thru a full regen cycle regularly:
- Since I only have a 15 minute 1-way commute, I would start a regen when I hit 100% full and always end up with a partial regen (need 20 "good" miles w/right conditions)
- I have probably been operating in a consistent 70% to 95% DPF Full state for most of this oil change
- This is exactly what my fear was (based on my driving routine/commute) and the reason why I bought my ODB adadpter + FORScan
- I'm guessing that DPF Full % is calculated by measuring the pressure differential before and after the Diesel Particulate Filter via sensors
- I need to verify these metrics exist in FORScan
- My Service Manager comfirm this is how they calculate DPF Full %
- If I am always running in a "near full" DPF state, I believe that this DPF near full condition is causing extra exhaust back pressure back into the engine (forcing more soot past rings)
- My theory is that Average DPF Regen Cycle Start % (what DPF Full % you start at) is tracked and used as one of the inputs in the Intelligent Oil-Life Monitor (IOLM) calculations
- I believe that my ~21 MPG average is due to my driving patterns + near DPF Full condition, while my MPG "records" are highway miles where I start at 0% DPF Full after a full regen
=> I have no hard evidence this theory, but this is my first attempt at trying to postulate what could be causing the difference in oil change intervals for some of us here on the forums
My "Jerry Springer Final Thoughts" on DPF Full % and "Partial" regens:
=> I think the DPF system on our F150s are on a much smaller scale than our HD brethren requiring much more frequent DPF regen cycles
=> I think Ford should enable DPF Full % on the instrument cluster by default, as everyone who hasn't FORScan-enabled this are flying completely blind WRT to DPF Full %
=> I also think Ford should be exposing OCR (Operator Commanded Regen) for those owners who don't do a lot of highway driving
=> I may start using manual OCRs in the parking lot at work to prevent my Partial DPF regen "death spiral" and to see if they help improve my shorter-than-expected oil change intervals
=> My prediction is that the #1 ownership issue for F150 PS Diesel owners will be issues surrounding blocked/clogged DPFs with vehicles dropping into "limp mode" because owners have no OCR capability
I will continue to monitor this closely to prove/disprove my theory and report back.
Great write-up, looking forward to any updates.