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Actually, in my case what the "Official Mopar" indicated above makes sense in my particular case (2018 Compass.) On long trips, several hundred miles on Interstate Highways at steady 70 mph, no oil consumption noted. Doing same or shorter distance around town (over several weeks), with suburban type "stop and go" traffic, is where I note my oil consumption. (Luckily, nowhere near the FCA "allowable" 1000 miles per quart threshold.) In conversations with my dealer's Service Advisor a year or two ago, he also mentioned that other owners were reporting the similar situation - namely higher oil consumption "around town" versus highway speeds.

In any event, anyone have a new TSB from FCA addressing this supposed remedy?
 

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On long trips, several hundred miles on Interstate Highways at steady 70 mph, no oil consumption noted. Doing same or shorter distance around town (over several weeks), with suburban type "stop and go" traffic, is where I note my oil consumption.
Interesting.

You know, if their general explanation is true/correct then its technically still possible that the heart of the issue still comes down to piston ring tolerances, its just that our understanding of it was slightly off and they are able to re-frame it as a different-sounding issue as a result.

Check out this article on crankcase ventilation systems: Crankcase ventilation system - Wikipedia

We (or at least I) had always kinda assumed that oil was coming UP, into the combustion area of the cylinders (due to loose rings), but it may very well be that its actually the force of combustion gasses going DOWN into the crankcase of the engine that kicks off this issue. The core idea being that these "looser" piston rings allow blow-by to happen much more than on other engines of the past. That would actually make more sense.

Excess crankcase pressure (blow-by) combined with an engine using pretty "thin" oil that is "sprayed" in several places in the motor as part of lubrication sounds like a recipe for aerosolizing oil and carrying it into the intake to be burned via the PCV system. That right there might be your full explanation, and it is still technically an issue with piston ring tolerances at heart.

The vacuum/PCV system that FCA is trying to name as the problem is probably doing its job to a T. When blow-by enters the engine crankcase you gotta get those gases out of there, and for emissions reasons they route those gasses into the intake to be burnt to reduce pollution.

If it were a problem with the PCV itself they would redesign it, or add a catch can maybe, but if their only move is to provide a software update that tweaks engine running and idling parameters to avoid whatever scenario exacerbates the issue the most then that means the PCV probably already works as good as it can, and excessive blow-by is the real source which again is piston rings and again would be a complete engine teardown to replace.

"I'd like to solve the puzzle!"

14686
 

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I got the W20 notice and scheduled my reprogramming for next week. We don't drive the car much but did just do an oil change so it will be interesting to see if this does anything. I haven't noticed abnormal consumption, but again, don't drive it too often.
 

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Received my Customer Service Notification letter today. Like the phrase: "... some vehicles may have an engine that consumers more oil than usual ..."
csn.JPG
 

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Would guess it’s a little in vain and wouldn’t expect a flash to change oil consumption but curious is anyone in Canada have this recall?
 

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I wonder, when they say "continuous stop and go driving" if they mean stop and go driving with the use of the ESS system? As many of you know I disabled my ESS permanently a couple years ago and even when it was enabled I was in the full-time habit of turning it off as soon as I started the car each day. I never really had oil consumption issues to speak of. Every great once in a while I would top off a pint before a road trip at most, and although I always check it 3-4 times on road trips I've never needed to add a drop of oil on any of the 3,000+ round trips we take to Washington and back 🤔

I do end up doing a lot of idling, mostly in the winter, because I use the remote start so so sooooo much in the winter. Virtually every start is via remote 5-10 minutes before I leave for work or anything (and on return trips as well). I don't think I've observed any excessive oil consumption in the winter... but like most people I don't track it scientifically either.

Who knows, maybe raising the idle from 750 RPM to 900 is enough to reduce the "sweet spot" where the blow-by happens the most, or vice versa, I'm not sure what they are adjusting.

I've been meaning to circle back with HPTuners and see if their latest updates allow reading my PCM (was not working previously, I sent in the debug and log info to them and they said they would work on it). If I could get a full read of my PCM before any such service department updates maybe we'd be able to suss out exactly what is being changed. I don't know if mine will even get the offer for the PCM update, though.
 

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Got my letter today. 2018 Latitude built 11/28/17, in service date, 3 years today, 1/15/18. 854 miles since I changed the oil 10/4/2020. Mostly local driving except for a 200 mile round trip to Cape May. Oil level is down about 1/2 pint. I also have the ESS disabled.
 
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