2015 Honda CR-V AWD excessive oil cunsumption

Messages
17,036
Location
Upper Midwest
After reading all posts, here is my plan:

1. Blackstone oil analysis
2. Check if a PVC valve change helped (need some more mileage)
3. If I am still there with the oil burn, will add some safe (?) additive (not engine flush) to the existing oil
4. Check if it helped
5. At MM ~6000 miles ( 4000 miles left) will change the oil with High Mileage oil 0W-20. I am hesitating switching to higher viscosity, at least not now.
What are you looking for with the UOA?
 
Messages
80
Yes, this is a DI engine. The fuel dilution issues with Honda engines, AFAIK, started with 2017 CR-V models with new engines. I have ordered a Blackstone oil analysis kit.
I've long postulated that fuel dilution is a significant contributory factor to the oil burning/stuck oil ring problem. The problem is not so much the dilution thinning the oil, it's when the condensed gasoline in the sump oil starts to re-evaporate as the engine comes up to temperature. If you know anything about the dynamics of multi-component vapour-liquid equilibrium, you realise that evaporating a lot of light hydrocarbons will always 'carry' with it, a tiny but significant amount of heavy lubricant base oil. This 'carried' oil is truly in the vapour phase & will sail past any physical baffles in the PCV/air intake system.
 
Messages
1,406
Location
Maryland
After reading all posts, here is my plan:

1. Blackstone oil analysis
2. Check if a PVC valve change helped (need some more mileage)
3. If I am still there with the oil burn, will add some safe (?) additive (not engine flush) to the existing oil
4. Check if it helped
5. At MM ~6000 miles ( 4000 miles left) will change the oil with High Mileage oil 0W-20. I am hesitating switching to higher viscosity, at least not now.
Sounds like a plan(y)
 

lk77

Thread starter
Messages
23
Change the oil and add one bottle of Rislone. It is not a flush. It may help unstick any carbonized rings. It reduced the oil consumption in my 2017 SantaFe which has VVT. It is a very safe product to use. Look it up.
Which Rislone product exactly do you suggest?
 
Messages
12,960
Location
North Carolina
Yes, this is a DI engine. The fuel dilution issues with Honda engines, AFAIK, started with 2017 CR-V models with new engines. I have ordered a Blackstone oil analysis kit.
Blackstone does not seem to have as good a reputation for measuring fuel in oil.
I would pull a sample after one of your typical drives. Don't pull a sample after a long drive, unless that is your usual.
You want to know how much fuel is there on the short trips.
 
Messages
80
There's one other thing I might suggest...

Honda seem to have a particular problem with fuel dilution & it occurred to me, they might be running their crankcases too cool, by setting their coolant thermostats at too low a temperature.

There may be a perverse logic to this. OEMs love ever thinner engine oils because they flatter their government mandated fuel economy/emissions numbers. However, when it comes to actual day-to-day running of those engines on thin oils, one way of mitigating against excessive engine wear (real or perceived) is to keep the oil at a lower temperature. You might practically achieve this by turning down the water coolant thermostat set-point (bulk oil temperature tends to follow coolant temperature). However, this might also promote fuel dilution, which in turn might, over the long-term, cause oil ring stick. In such a circumstance, I might fit another thermostat.
 
Messages
25
Location
Toronto, Ontario, Canada
Personally, I’d try these steps in this order (move to the next step if the current doesn’t improve consumption) before any additive or piston soak:

1) Try a different brand, but keep it a synthetic of the same viscosity
2) Try a high mileage synthetic of the same viscosity
3) Try increasing the viscosity slightly (eg. Xw20 to Xw30) but keep it synthetic
4) Try running a ”conventional“ of either the original or increased viscosity
 
Messages
1,406
Location
Maryland
Which Rislone product exactly do you suggest?
Rislone engine treatment concentrate in the yellow bottle. Available at Walmart. If they don't have the concentrate get the regular. It is just a larger amount.
Screenshot_2021-02-12 rislone engine treatment - Google Search.jpg
Screenshot_2021-02-12 rislone engine treatment - Google Search.jpg
 
Messages
2,238
Location
Paradise of Florida
At this mileage/age, change the PCV valve.

No fan of MM intervals. Sorry, if it worked so well, would the car be an oil burner? So, change your oil every 6 months or 5k miles, whichever comes 1st. Don't wait for the MM.

I would step up to a synthetic 5w30 and use a synthetic media oil filter.

M1 filter isn't synthetic media and not worth using.

High mileage oils are 'marketing' at best... don't expect anything extra from them. And, you don't have to wait to a certain mileage point to use them. They can be used on a brand new engine. Yours isn't doing so well regardless of the mileage. So, besides stepping up to a synthetic 5w30, use a HM synthetic 5w30.

VVT won't be ruined by oil flushes or magic. Mobil1 isn't the best. If it was, why are you burning 1qt every 1000 miles?

Here is a list of additives with links.... pick one for each oil change interval and use it as the 1st bottle top off.

1. Don't bother with UOA. Not needed with safe/sane interval unless you are looking for something specific, like coolant form blown headgasket.
2. There is no checking/testing/shaking/blowing a PCV. Just replace it!
3. Yes, use an additive NOW and pick one for every interval. Hoping for decarbon'ing the rings. No additive fixes excessive wear or engine damage.
4. Just keep driving and keep oil level full.
5. Ignore the MM and change oil/filter more often.
 
Messages
1,259
Location
NC
- Switch to higher viscosity Mobil1. IT WILL NOT cause a single oil related issue with VVT/VTEC, but it will help battle Fuel DIlution. I would consider Mobil1 5W-30 HM, or Mobil1 0W-40. There is a study that was done and posted here where Mobil1 showed great cleaning abilities. And with M1 0W-40 being their most additive loaded flagship oil - that would be the one I'd run. As a matter of fact - that is the one I run now in my oil burning 20 year old Honda CR-V trail/camper rig.

- Next Oil change add a bottle of Rislone Concentrate. If improvement is noted - keep using Rislone until desired results are achieved, or improvements stopped happening. Also get some BG EPR. Run that for an OCI or two.

It will take some miles, but if after all this you still have bad consumption - engine rebuild is your only bet. Also inspect your engine thoroughly for oil leaks if you haven't yet.



Screen Shot 2020-10-07 at 1.19.07 PM.png
 
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Messages
2,090
Location
GA
I don't think there is too much you can do; Our 16CRV, we bought it a brand new, and I noticed the oil subsumption right from the get go; I replaced PCV at 40K now we have 72K on it; Again the consumption in our case its a little north of 1Q id say; Also I have another K24W in my Accord and it doesn't seem to burn oil between OCI but I am practicing change at 5K anyway; My wife drives CRV and I know she is harder on the car than myself

So you can change the brand of oil or add different viscosity but in a nutshell that's it, of course if you don't want to spend extra $$$ on it; Honestly, I would not use any aftermarket additives in the engine; We drive our CRV to long distances and pretty much everywhere because we plan on replacing it first due to its oil consumption

that's PCV that ultimately did not need to be replaced
IMG_1636.jpeg
 
Messages
15,873
Location
N.H, U.S.A.
You have very likely been afflicted by late onset oil control ring stickage. It's a problem caused by the volatile front end of your oil's base stock recycling through your PCV system, being burnt & the resultant gummy residue causing one of your oil control rings to get stuck flush in its groove.

There's no easy fix. You could try moving to an oil with a lower volatility but these are few & far between in the US. If you can get your hands on a cheap, Middle Eastern, Group I 20W50 it might help but that's probably not realistic. Maybe an overnight piston oil soak might free things up?

Or just accept this is how things are & keep adding oil. Sorry I can't be more helpful.
This mechanism you describe does not makes sense.

Most PCV is filtered inlet port air, ring bypassed upper volatiles and fogged oil vapour.

Also the PCV is just a metering port, that pill is a anti-backfire device. I have never serviced a stuck one, and that would be in
a completely neglected engine with no oil change for 2 years.
In carburetor engines, we would just clean the old metal ones in the part washer and reinstall.

The % of PCV as an inlet charge is very small. The constituents will be completely burnt in the combustion cycle.

Stuck rings are typically caused by low engine loading with brief and infrequent high loading, then and poorly formulated or expended oil.
Many engine designs have experimented with low tension ring designs that afford poor sealing.

If you DO have a hot stuck ring its likely #2 and #1; not the oil control which has generous ports for the clean filtered oil to cycle through.

I would call Honda Customer service and see what they can do for you. But in the mean time change oil brands and substitute a quart with one of higher grade. Likely may not work but worth a go and the engine will likely enjoy it,
 
Messages
1,952
Location
Ontario, Canada
Honda had issued a bulletin stating the issue was caused by a combination of low quality fuels and driving too aggressively before the engine has fully warmed up, which will cause the engine to run excessively rich. Change the oil every 5k, do not follow the MM, do not let it idle when cold for extended periods, use top tier fuel only, and drive it gently till fully warmed up. Try not to short trip it. But all this is basically true for all cars.
 
Messages
12,306
Location
OH
Agree with above and try some Gumout Regane HM fuel system cleaner, Chevron Techron, Redline Sl 1, etc regularly esp if not using TT fuel. Try two back to back treatments.
 
Messages
35,628
Location
NY
Unfortunately complaining to a Honda dealer about oil use for a vehicle will most likely get you nowhere, except the story about it being normal. At least that's how it was back when I sold cars at two different Honda dealerships. Since your warranty is up and my comments don't apply, I'd run either Mobil 1 ESP 0W30 or 5W30 in it and see what happens. Being OCD I might even try one of my favorite "engine cleaners" [to remain nameless], or a piston soak if the switch in oil doesn't help.
 
Messages
80
This mechanism you describe does not makes sense.

Most PCV is filtered inlet port air, ring bypassed upper volatiles and fogged oil vapour.

Also the PCV is just a metering port, that pill is a anti-backfire device. I have never serviced a stuck one, and that would be in
a completely neglected engine with no oil change for 2 years.
In carburetor engines, we would just clean the old metal ones in the part washer and reinstall.

The % of PCV as an inlet charge is very small. The constituents will be completely burnt in the combustion cycle.

Stuck rings are typically caused by low engine loading with brief and infrequent high loading, then and poorly formulated or expended oil.
Many engine designs have experimented with low tension ring designs that afford poor sealing.

If you DO have a hot stuck ring its likely #2 and #1; not the oil control which has generous ports for the clean filtered oil to cycle through.

I would call Honda Customer service and see what they can do for you. But in the mean time change oil brands and substitute a quart with one of higher grade. Likely may not work but worth a go and the engine will likely enjoy it,

The primary purpose of any PCV system is to recycle partially burnt gasoline & condensed water vapour, that can accumulate in sump oil. There's really no problem with this. The fuel burns cleanly, water leaves as steam & everything goes out the exhaust pipe. Job done. Sorted!

However the system was never designed to burn oil & therein lies the problem. Modern engines (especially GDIs) with low tension rings seem to dump more fuel into the sump (especially when it's cold outside). That fuel can only exit the crankcase one way; via the PCV valve & into the air intake. If you couple higher rates of fuel recycling with thinner & directionally more volatile engine oils, then you increase the rate of 'oil carry'. This is Boyle's Law & Charles's Law made manifest. If you've ever refined oil or designed crude distillation columns, you will grasp this in a heartbeat. If you haven't, it gets trickier to picture what's happening.

Yes, there's usually some kind of physical baffle system, designed to separate the bulk of the oil droplets from the gaseous blow-by & re-evaporated fuel/water. However any oil that has entered the vapour phase cannot be knocked-out by a physical baffle. If life was that easy, I could solve global warming at a stroke by pumping air through a physical baffle and sitting at the end of the baffle with a big bucket to collect all the carbon dioxide!

If the hot recycled oil actually stayed in the vapour phase, it might be easily to burn but it doesn't. As soon the gas stream traversing the PCV valve hits the cold intake air, the oil condenses back into liquid droplets which will resist complete burning. Not only that but the induced swirl inside the combustion chamber throws the droplets towards the bore (think of it as a centrifuge) where combustion is worst & where some gummy deposits inevitably end up getting caught up in the ring pack.

There are two distinct phases to this problem. Usually, in the first phase, oil consumption is tiny but significant. It may last 50,000 miles of engine operation. The build up of gunk in the oil control ring is slow but progressive. In this period, the oil control ring can still 'bounce back' despite the presence of large amounts of gunk in the groove.

But a point comes where the ring does get properly stuck in its groove & to all intents & purposes, that ring is effectively just part of the piston. Oil is thrown up or sprayed up under the piston crown but there in now no primary bulk oil scrape (sorry, can't think of a better way to describe the process). Now some of that 'unscraped oil' can find it's way up the side of the piston under hydraulic pressure supplied by the downward motion of the piston itself. It can now start traversing the 2nd & Top rings, most likely taking the line of least resistance through the ring gaps. Now the oil has a direct route to the combustion chamber. It's a bit like having a busted valve seal. From 50,000 miles onwards, you're likely to see a much higher rate of oil consumption because the oil loss is from underneath as as opposed to 'over the top'.

This may not make sense to you but it makes perfect sense to me & reflects much of the oil behaviour I'd repeatedly see running engine tests like the Sequence IIIG & Peugeot TU5.
 
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