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Fuel and Oil Refresh Mode

135K views 535 replies 86 participants last post by  Mllcb42  
#1 ·
So, put gas in my Sahara for the first time on the weekend. Was able to travel just over 800km (~500 miles) on the first tank, with my consumption at about 8.8L/100km and still dropping. I'm pretty happy with that so far.
Ran into this issue though - since I filled up with "premium" gas on Saturday, my Jeep goes directly into "Fuel and Oil Refresh Mode" once started. Wtf?? It will only run on gas now.
Wondering if anyone else has experienced this or not?
The manual suggests adding at least 4 gallons of gas to get out of it ( "if" the mode was enabled because of stale gas).
Otherwise, it will turn off once the gas light comes on after burning through the current tank of gas.
If it was triggered because of engine lubrication then it is supposed to turn off after 20 min of continuous engine running.
I've tried reseating the fuel cap, switching through all driving modes, but that's about it...what else can a person do?
Tonight I will add some more gas (just didn't have time to burn through a quarter tank or so yet).
FIrst thought was bad gas possibly? I mean, I guess its possible but come on...is this thing going to be that sensitive?
Will give an update later this evening after adding more gas.
 
#2 ·
It did that after adding premium fuel? Now that’s interesting. We’ve had some discussions in the Wrangler 4XE Fans group about premium fuel. The gas only owners manual says that you can use either low octane or premium. But the 4XE supplement just suggests using 87 and we’ve wondered about that. Sort of wondering if the premium fuel causes issues with some sensor or something.
 
#5 ·
Interesting...My guess is this has more to do with maintaining fresh fuel and circulating engine oil than it has to do with the grade of fuel (i.e. premium vs. regular). As the 4xe is biased to run on electric, for short trips less one could be in a situation when the gas engine hardly ever runs which applies to my use case. Gasoline and oil both have a shelf life (gasoline immediate vs. oil once put into use) and most areas have varying fuel blends depending on the season and ambient temperatures. It would not surprise me if there is a 4xe algorithm that tracks gas engine usage and a "fuel and oil refresh" mode to burn through stale fuel to prevent problems associated with stale gas and oil. I am trying to encourage my 4xe to run through the first tank of gas and found that moving the shifter into 'manual shift sport mode' is the only way to keep the engine running in an attempt to burn through my gasoline. Once I empty the tank, I will add Stabil to a full tank of premium fuel or ethanol-free marine gas and then let the 4xe follow it's regular programming.
 
#7 ·
Perhaps that gas wasn't as premium as it should have been? I've heard plenty of stories about water in the fuel from the station.

The difference in the manuals caught my interest too. 87 seemed to be the recommended but then it also said 91 or higher was beneficial to the 2.0, especially in hot climates, in the original manual.

It may just be the engine doesn't have to work as hard with the hybrid setup so the engineers felt it wasn't worth it in this powertrain? Although, isn't ECU timing bigger on the low/mid end with higher octane?
 
#9 ·
There is some great engineering in this system. I've known a couple people that have have gotten bad gas, to the point there was engine damage was done. I had a co-worker who had his BMW X5 in the shop for a whole month after getting bad gas. Perhaps the software caught something?
 
#10 ·
Hello, all.

We understand why this message may be concerning, but the vehicle is operating as designed.

For some clarity, "Fuel and Oil Refresh" mode is a function that monitors the oil dilution and stale fuel over time. Every time the engine starts, fuel that is not burned can accumulate oil; in Hybrids the engine stop and starts are more frequent and the fuel can accumulate oil at a faster rate. That said, the "Fuel and Oil Refresh" function forces the engine to to refresh and thus avoids the accumulation and promotes the dissipation of the fuel in the oil.

For more information on this, I will link the "Hybrid Supplement" Manual and the accompanying page below.

If any of you have further questions or concerns, we recommend first reviewing the Owner's Manual and then speaking with your servicing/selling dealer.

Thanks!
Jeep Cares


441

442
 
#30 ·
What if you don’t drive more than the 20 miles needed for the oil refresh. Mine has been stuck in that mode for four days with no sign that it will end and it is destroying my gas mileage.
Hello, all.

We understand why this message may be concerning, but the vehicle is operating as designed.

For some clarity, "Fuel and Oil Refresh" mode is a function that monitors the oil dilution and stale fuel over time. Every time the engine starts, fuel that is not burned can accumulate oil; in Hybrids the engine stop and starts are more frequent and the fuel can accumulate oil at a faster rate. That said, the "Fuel and Oil Refresh" function forces the engine to to refresh and thus avoids the accumulation and promotes the dissipation of the fuel in the oil.

For more information on this, I will link the "Hybrid Supplement" Manual and the accompanying page below.

If any of you have further questions or concerns, we recommend first reviewing the Owner's Manual and then speaking with your servicing/selling dealer.

Thanks!
Jeep Cares


View attachment 441
View attachment 442
 
#12 ·
Hi guys, mines been in refresh mode for about 5 days even though I had ran the engine for more than 20 min in stop and go the other day.
I can start it in electric, but as soon as the engine kicks in for any reason (usually accelerating to fast), it goes into refresh. My normal commute is only about 15min, I run hybrid, but it stays mainly in electric (80/20). Maybe I need to go on a longer drive.
 
#13 ·
UPDATE: I drove the car home from work, about 20 min, and was still getting the fuel and oil refresh. Getting frustrated I called Jeep and of course they didn't know how long it would take to reset and told me to bring it in. I figured all service would do is a longer drive as a test. SO, I kept it in idle in the driveway for about 15min, then drove about 30min to run an errand. On the way home it finally cut to electric while at low speed. I pushed the electric button to confirm and it looks like its resolved. That just seems like an excessive amount of time and effort to clear the refresh. I guess the moral of the story is if you get the notice, drive the car for more than 30min in one go to clear.
 
#14 · (Edited)
We got this message yesterday, started, flashed up, immediately fired up the ICE (even though it was in Hybrid mode), hahaha, I was like, "WTF is all the noise?" :D

Wife took the little G to the dentist, short trip, maybe 8-9 miles, and she said just before she got there, the ICE shutdown, back to glorious battery only. Today, since there was the threat of rain (we leave the top off 98% of the time ...), she took the Tesla, and I popped up to the grocery for a couple of supplies (figured I could make the 3-1/2 mile round trip between rain, I did!), stayed on the whole time.

Here's the thing: we haven't driven it very much, and in just sat for the last 10-11 days or so (we were traveling in the other car), and this is the same tank of gas we've had in it for like 2 months (it's at about 3/4).

I guess I need to think about using it more, gas sitting in the tank for weeks, maybe some stabilizer[?]
 
#32 ·
OK, thought I'd bump this thread.

My previous encounter with this message from two months ago:




And then I resolved it later that week:

Oh, update on my status :)

So it was still running ICE only, but my drives were down to the grocery and back, like 3 miles round trip :D So a couple of days ago, I ran it up to the Gate station ~8 miles north of us, it never kicked into battery mode, I stopped, topped it off with some 89, about 1/2 a tank, when I turned it back on - poof - normal operating status, no ICE, battery only, could be toggled between the different modes, ICE kicked on with a D>M shift and off as expected.

So not sure what the actually trigger was: another 16 miles, some heavy left foot, opening the gas door, a notable change in the amount of gas, but it's running like it used to.

Again, it started then it sat with about 1/2 a tank, not driven for about 2 weeks.

And it's doing it again over the last 7-10 days, I've been driving it a little more, ran it down to 3/4 of a tank, haven't topped it off yet.

I think this system is being a little too aggressive, it should either do it incrementally, like every start, run the engine for 4-5 minutes, then let the normal modes work. Plus, there seems to be some kind of different logic for this mode, that's not indicated - from the manual:

If the vehicle enters Fuel and Oil Refresh Mode, due to fuel which has been in the fuel tank for a long period of time (becoming stale fuel), the engine will run whenever the vehicle is operational (no electric only operation) until the low fuel level warning is activated. It is also possible to exit the Fuel and Oil Refresh Mode sooner by adding a minimum of four gallons of new fuel to the vehicle’s fuel tank.
So if it's the fuel-use-timer, you have to run all the gas out, or run down so you can add at least 4 gallons. But it might be triggered by the oil-engine-lubrication, again per the manual:

If the vehicle enters Fuel and Oil Refresh Mode to maintain engine lubrication, adding fuel will not exit the mode sooner. If the vehicle enters Fuel and Oil Refresh Mode to maintain engine lubrication properties, the engine may run for a period of up to 20 minutes when fully warm whenever the vehicle is operational (no electric only operation). If the vehicle is shut down before conditions to exit the refresh mode have been satisfied, the engine may run for additional time on subsequent trips.
I'm assuming, since we drove it for 30+ minutes continuously the other day (drove out to the Apple Store :) ), 35 miles each way, that 20 minute switch would've been hit, so it must be the fuel-age-use-timer logic.

And if that's the case, that's kicking on too soon, it's not doing any kind of real analysis, only some kind of "you've used 1 gallon in 3 weeks, your fuel is bad" trigger. I wish I knew the actual values, i.e., how much fuel needs to be consumed over what period, it would allow me to plan for gas only usage to prevent this, but it also means that we've got a bit of a "forced" extra cost since we could easily run battery 99% of the time.

Hahaha, not sure if I'm just bitching out loud, seeking an answer, or what, but I feel better :D
 
#15 ·
I put stabilizer in and got this message for about 4 days straight of short trips under 20 miles. It just keeps burning my SeaFoam & 93 octane gas like it’s stale. It’s used up 1/3 tank before I said screw this, and put 5 gallons of 87 octane in there. Over 4 gallons is supposed to stop the fuel and oil refresh. We will see next time out if it just burns electric for me. No use putting in 93 octane if it’s gonna just burn it up for no reason. I’ll just use the additive once in a while.
 
#16 ·
I recall seeing elsewhere on a thread or in one of the expert videos that the function of burning off the 'stale fuel' is based on time and the fuel level (i.e. having not added sufficient 'fresh' fuel). There is no intelligent sensor that actually determines the quality of the fuel - it is just burned off to prevent all of the issues that arise from stale fuel regardless of additives and stabilizers. I still think adding the stabilizers will help keep the ethanol from separating and avoid other issues that arise from stale fuel.
 
#19 ·
@JeepCares
Thank you for the fuel/oil explanation. This kind of interaction and feedback is helpful. As well as posting up the hybrid supplement which doesnt seem to be available under the My Mopar App. Just the standard 2021 Jeep Wrangler manual is available.

Could you define "extended periods of time" for us? Or at least ballpark it. Are we talking days of no engine operation or weeks or months to have created conditions for stale fuel. Thanks.
 
#21 ·
Oh, update on my status :)

So it was still running ICE only, but my drives were down to the grocery and back, like 3 miles round trip :D So a couple of days ago, I ran it up to the Gate station ~8 miles north of us, it never kicked into battery mode, I stopped, topped it off with some 89, about 1/2 a tank, when I turned it back on - poof - normal operating status, no ICE, battery only, could be toggled between the different modes, ICE kicked on with a D>M shift and off as expected.

So not sure what the actually trigger was: another 16 miles, some heavy left foot, opening the gas door, a notable change in the amount of gas, but it's running like it used to.

Again, it started then it sat with about 1/2 a tank, not driven for about 2 weeks.
 
#22 ·
This - "a notable change in the amount of gas"

Yep, that is what I gathered from Dan. His KISS reference was that there are no sophisticated fuel quality sensors, but simple metrics used to invoke the engine to start and run. It knows how much fuel is in the tank, it knows the last time the engine was ran and for how long, and it knows when more fuel gets added to the tank. As little as 4 new gallons may be enough.

His other comments were in regards to fuel dilution of the engine oil. Cold engines allow some fuel to make it's way past the rings and end up in the oil. The engine has to be ran to heat up the oil, sometimes up to 60 minutes, in order to get the fuel in the oil hot enough to evaporate and get reburnt through the PCV.
 
#27 ·
Great question and I would really like to know that answer also. The way I understood it, 90 days is what Dan had referenced in @Wrangler4XEFan 's interview as a general timeframe for potentially stale fuel or water condensation buildup in fuel tank that they are wanting to see cycled through the system. That is my interpretation of the information presented, not first hand knowledge.

My question is, if the ICE seems to be running alot and there is no Fuel and Oil Refresh notification, how do we know if it is operating normally or if there is an abnormal issue but not severe enough to set a MIL? Just like an earlier conversation about wondering if the ICE kicks in if the battery coolant temperature reached a certain safety limit in order to take a thermal load off the battery system. How do we know, and how can we find out?

I am also under an assumption that the climate system probably also invokes the ICE. I would venture to guess that a heat request outside a set threshold from the current cabin temperature may pull in the ICE in addition to the electric heater to meet that request more quickly. All speculation, but that's what I would do.

Similar to you, I am finding that my ICE frequently starts up and runs without any apparent reason why an no notifications even if it has a full battery and the vehicle is first placed in Run. It also randomly occurs at relatively low speeds from time to time and of course always in Hybrid Mode. Sometimes I can select Electric Mode and maybe the ICE will instantly or eventually turn OFF, sometimes it says "Not Available" ?

@JeepCares
If there are any experts available that are willing to solve some of these questions that would be awesome!