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So my wife and I bought a 2018 Cherokee Latitude Plus 4x4 brand new back about 3 years ago now. From day 1 is has consumed large amounts of engine oil. I complained to my dealer who said to give it 20,000 miles or so and see if the piston rings seat and consumption decreases. We're now just past 40,000 miles and oil consumption has slowed but has not stopped. I just put another quart in it a few days ago.

Today I got a letter in the mail that appears to be a recall/TSB notice on this vehicle. It states that they've recognized the oil consumption issues and they will repair the vehicle for free because our Jeep falls within the date range of the issues. However, the fix they talk about has to do with updating the PCM software.

Can somebody here explain to me how a software update will fix what I assumed is a hardware problem?
 
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How many miles do you go on a quart?
 

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How many miles do you go on a quart?
I change the oil approx every 8,000 miles and I usually put quite a few quarts in between. Honestly I need to let my dealer do an oil consumption test but they're 35 minutes one way from my house and it's not convenient.

One time early on in ownership I made the mistake of going a few thousand miles without checking it and the oil was so low it wouldn't even register on the dipstick. That's when I realized there's a problem.
 
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Well, you and I know that 2000 miles per quart is not good, and usually encountered above 200,000 miles on an engine. However, I keep reading about how some manufacturers stonewall customers on this and claim that this is normal. It's not. My wife bought a new 2012 Chrysler 200 with 2.4L engine, and I have a used 2011 that I bought at 95K miles, now has 133K miles. Each goes about 7,000 miles on a quart. No visible leakage at all, zero drips under the cars. And lest they say this depends on the era of the vehicle, my 1992 Dodge Daytona with 2.5L engine originally went nearly 10,000 miles on a quart when new, and at 308K miles when it rusted out, would still go over 2000 miles on a quart. Original engine, never apart.
Good luck with the good fight.
 

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My sister has a 2.4L Multi-Air Dart, and she's only had any "consumption" (people assume it was me not tightening everything down right after doing her oil change) once. Never had it again, and she's at like 118,000 miles on the sucker.
 

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My sister has a 2.4L Multi-Air Dart, and she's only had any "consumption" (people assume it was me not tightening everything down right after doing her oil change) once. Never had it again, and she's at like 118,000 miles on the sucker.
So do, some don't. Those that do use oil can be pretty thirsty.
 
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So my wife and I bought a 2018 Cherokee Latitude Plus 4x4 brand new back about 3 years ago now. From day 1 is has consumed large amounts of engine oil. I complained to my dealer who said to give it 20,000 miles or so and see if the piston rings seat and consumption decreases. We're now just past 40,000 miles and oil consumption has slowed but has not stopped. I just put another quart in it a few days ago.

Today I got a letter in the mail that appears to be a recall/TSB notice on this vehicle. It states that they've recognized the oil consumption issues and they will repair the vehicle for free because our Jeep falls within the date range of the issues. However, the fix they talk about has to do with updating the PCM software.

Can somebody here explain to me how a software update will fix what I assumed is a hardware problem?
it's an interesting read. This is a very odd statement than makes it sound like a phyical problem is being fixed by software:
"that will address the manufacturing variances that could lead to an abnormal use of excessive oil. To do this, your dealer will inspect the software level of the Powertrain Control Module (PCM) in your vehicle, and, if necessary, reprogram the PCM."
 

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it's an interesting read. This is a very odd statement than makes it sound like a phyical problem is being fixed by software:
"that will address the manufacturing variances that could lead to an abnormal use of excessive oil. To do this, your dealer will inspect the software level of the Powertrain Control Module (PCM) in your vehicle, and, if necessary, reprogram the PCM."
This sounds like the half-dozen "reflashes" of the software on the KL 9-speed until they figured out that FCA went cheap on internal parts.
 

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So do, some don't. Those that do use oil can be pretty thirsty.
Which is the issue with so many FCA quality problems;.....rather than being a consistent failure, it is intermittent and difficult to diagnose.
 

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So my wife and I bought a 2018 Cherokee Latitude Plus 4x4 brand new back about 3 years ago now. From day 1 is has consumed large amounts of engine oil. I complained to my dealer who said to give it 20,000 miles or so and see if the piston rings seat and consumption decreases. We're now just past 40,000 miles and oil consumption has slowed but has not stopped. I just put another quart in it a few days ago.

Today I got a letter in the mail that appears to be a recall/TSB notice on this vehicle. It states that they've recognized the oil consumption issues and they will repair the vehicle for free because our Jeep falls within the date range of the issues. However, the fix they talk about has to do with updating the PCM software.

Can somebody here explain to me how a software update will fix what I assumed is a hardware problem?
Hello, the oil consumption concerns are caused from vacuum being created in the cylinders during deceleration. Software changes the events, internal to engine, that lead to creation of vacuum.
If you need any help setting up an appointment, feel free to let us know.

Kaitlin
Mopar Cares
 

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I got the letter for my 18 Compass.
It mentions stop-start and city driving as being part of the issue. My Jeep 2.4 doesn’t use oil between changes.
 

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My 18 Compass uses around a litre for every 3000 kms. Just on the edge of what FCA says is acceptable. I've checked with the dealer though, and so far it's not covered under any recall. Maybe because it's Canada?
 

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My 18 Compass uses around a litre for every 3000 kms. Just on the edge of what FCA says is acceptable. I've checked with the dealer though, and so far it's not covered under any recall. Maybe because it's Canada?
It’s not a recall (yet anyway) but a “satisfaction campaign”.
 

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It’s not a recall (yet anyway) but a “satisfaction campaign”.
Correct, I read the letter again and this is a "customer satisfaction notification". I have an appt with my dealer this morning to get the "fix" done to the Jeep and it'll be interesting to see whether this really fixes the issue. I'll update in a few thousand miles.....
 
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Hello, the oil consumption concerns are caused from vacuum being created in the cylinders during deceleration. Software changes the events, internal to engine, that lead to creation of vacuum.
If you need any help setting up an appointment, feel free to let us know.

Kaitlin
Mopar Cares
How does a gasoline engine run without vacuum? Or better yet, how do you eliminate vacuum short of never allowing the piston to move down and draw in air and fuel?
This explanation does not make sense.
 

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How does a gasoline engine run without vacuum? Or better yet, how do you eliminate vacuum short of never allowing the piston to move down and draw in air and fuel?
This explanation does not make sense.
I was thinking about that as well.

The next question is how does this change the performance of an already anemic engine?
 

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Didn't know you needed vacuum when you decelerate. With "Interactive Decel Fuel Shut Off (iDFSO)", or atleast like every vehicle in the past decade not putting fuel into the engine during decel by software changes, you'd think the idea would be not not draw vacuum in during that time. I imagine it's possible to prevent this with VVT, by really screwing up the timing of the valves opening & closing, to prevent the vacuum to occur & just have crank/piston assembly's keep on rotating while the valves open and close at times when vacuum wouldn't be created.
Makes sense to me. Then again, I'm no engineer.....
 

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Didn't know you needed vacuum when you decelerate. With "Interactive Decel Fuel Shut Off (iDFSO)", or atleast like every vehicle in the past decade not putting fuel into the engine during decel by software changes, you'd think the idea would be not not draw vacuum in during that time. I imagine it's possible to prevent this with VVT, by really screwing up the timing of the valves opening & closing, to prevent the vacuum to occur & just have crank/piston assembly's keep on rotating while the valves open and close at times when vacuum wouldn't be created.
Makes sense to me. Then again, I'm no engineer.....
Even during deceleration, you are still running the engine. The piston doesn't stop moving up and down (the piston moving down is pulling in air and fuel too burn) which is as necessary (at different levels) at idle or deceleration as the engine must continue running.
 

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Even during deceleration, you are still running the engine. The piston doesn't stop moving up and down (the piston moving down is pulling in air and fuel too burn) which is as necessary (at different levels) at idle or deceleration as the engine must continue running.
I imagine it's possible to prevent this with VVT, by really screwing up the timing of the valves opening & closing, to prevent the vacuum to occur & just have crank/piston assembly's keep on rotating while the valves open and close at times when vacuum wouldn't be created.
Already said that. My idea was using VVT to open/close the valves at a different time If the piston is on intake, combustion, or exhaust stroke. The valves are open during these events, particularly the intake, which draws everything in with vacuum. While I can't imagine you can completely stop actuating the valves to have them remain closed, you could probably alter timing to prevent the intake stroke from using natural vacuum to bring in air. Piston's continue the strokes, but the natural vacuum from opening and closing the valves could probably be altered. If done improperly, I'd also like to imagine it might bring more oil through certain area's and cause the oil to get burned, causing the TSB.
 

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Opening the throttle under decel might decrease Engine vacuum.

Ford recently fixed a head gasket issue with software.

Thanks
Randy
 
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