2014 Mazda 6 - 0W-20 with Fuel Dilution

[jwagner]

Greetings, long time visitor here, first post, and for that matter, my first UOA. We bought a shiny new gas-powered Mazda6 in October, now with 2,500 miles. Did the first oil change after break-in at 1500. Checked the oil the other day and it was about a quart high and smelled badly of gas so I changed the oil ASAP and sent a sample to Blackstone. I think the dealer overfilled it at the last change, but not that much.

Results are back - fuel % at 4.8% with only 828 miles on this oil change. We're in Wisconsin and had a long stretch of sub-freezing weather, and the car is pretty frequently driven short distances, but if this is normal for a direct injected car in a northern climate there's a problem. Car has no indication of any malfunction, gets 38mpg on the highway and otherwise we're really happy with it. But I'm guessing that the fuel % will result in reduced engine longevity.

I'll call Mazda on Monday. Being an engineer, I'd like to get in touch with somebody technical, as opposed to working with a service writer at the local dealer, but have no clue how to do that.

Here's the results:

OIL Mazda 0W20
MILES IN USE 828
MILES 2,517
SAMPLE TAKEN 3/20/14

ALUMINUM 5
CHROMIUM 0
IRON 8
COPPER 10
LEAD 0
TIN 1
MOLYBDENUM 164
NICKEL 0
MANGANESE 1
SILVER 1
TITANIUM 0
POTASSIUM 1
BORON 89
SILICON 16
SODIUM 2
CALCIUM 896
MAGNESIUM 1175
PHOSPHORUS 696
ZINC 812
BARIUM 3

INSOLUBLES 0.1
WATER 0
FLASHPOINT ºF 290
SUS VIS 210ºF 45.6
cSt @ 212ºF 5.92

Opinions, suggestions, pointers welcome.

Jim

 

[Barkleymut]

im guessing you will jave to just go thru the local dealer. Bring the uoa along and politely demand to know exactly why you have so much fuel in the oil.

just curious when is the last time this car reached normal operating temp?

 

[simple_gifts]

I would do a UOA @ the end of the summer.

Short trips, subzero temps and there is fuel in the oil?
"Severe service" is exactly that.


Even my OM of my echo indicates one will find this.

 

[Quattro Pete]

Originally Posted By: jwagner
Checked the oil the other day and it was about a quart high

If the oil level was a quart high, you'd have a lot more than 4.8% of gas in there.

Quote:

We're in Wisconsin and had a long stretch of sub-freezing weather, and the car is pretty frequently driven short distances, but if this is normal for a direct injected car in a northern climate there's a problem.

I'd say the result isn't great, but not overly out of norm considering it's a DI engine driven short trips in very cold weather.

 

[Pablo]

Tell us exactly how you sampled the oil. How hot was the car? How long had it been run and idled before sampling?

 

[Food Scientist]

Originally Posted By: Quattro Pete

Checked the oil the other day and it was about a quart high

If the oil level was a quart high, you'd have a lot more than 4.8% of gas in there.

How do you know how much oil was in there to begin with to conclude that 1 qt overfill on the dipstick isn't 4.8% fuel?

 

[SF0059]

Was the car highway driven for 20 minutes per Blackstone's instructions?

 

[Quattro Pete]

Originally Posted By: SVTCobra
How do you know how much oil was in there to begin with to conclude that 1 qt overfill on the dipstick isn't 4.8% fuel?

He said he did his previous oil change, so presumably he knew what he was doing and did not overfill it while doing so.

His oil capacity is 4.8 qt. If he's 1 quart high now, then that would mean over 17% fuel.

Then again, the 4.8% that Blackstone gave him is just a guess since Blackstone doesn't actually measure fuel dilution.

 

[Eddie]

This is the first Mazda SkyActiv engine UOA that I have seen with a fuel dilution issue. Sounds like a stuck open injector or something else is wrong for sure. The wear values don't look bad for an engine that is not broken-in yet. Ask Blackstone to repeat the analysis, incase something in the lab got messed up. Ed

 

[Food Scientist]

Originally Posted By: Quattro Pete
Originally Posted By: SVTCobra
How do you know how much oil was in there to begin with to conclude that 1 qt overfill on the dipstick isn't 4.8% fuel?

He said he did his previous oil change, so presumably he knew what he was doing and did not overfill it while doing so.

His oil capacity is 4.8 qt. If he's 1 quart high now, then that would mean over 17% fuel.

Then again, the 4.8% that Blackstone gave him is just a guess since Blackstone doesn't actually measure fuel dilution.


He said he had it changed but did not mention he changed it himself. Also says he thinks the dealer overfilled it.

 

[Quattro Pete]

You're right. I missed that tidbit.

 

[vinu_neuro]

Originally Posted By: Pablo
Tell us exactly how you sampled the oil. How hot was the car? How long had it been run and idled before sampling?
Originally Posted By: SF0059
Was the car highway driven for 20 minutes per Blackstone's instructions?


I've wondered this for such usage. I'd imagine that the user would want to take a sample the way the car is used. If the car only sees short trips, removing all the fuel from the oil before sampling wouldn't be representative of the lubricant condition the engine sees.

 

[jwagner]

Answering a couple of questions -
The dealer did the first change and I recall looking at it afterwards and wondering why they overfilled it, but at that point it wasn't a quart over or I would have brought it back to them. So no, I'm pretty sure that extra quart isn't all gas, or it would be more like 16% fuel, right?

The car was run for fifteen to twenty minutes before the sample, in two trips. To the dealer and to get Mazda (Peak) oil which just took a couple of minutes, then off to the oil change place where they put it up on the rack and drained the oil and took the sample pretty much immediately. Given the strong gas smell of the oil, I'm surprised it's as low as 5%.

And yes, the car does get up to temperature and run on the freeway. Two weekends ago we did an hour and a half each way to Madison and I'll grab the 6 if I'm running across town on the freeway. Keep in mind that we're coming off a severe winter with 34 days below zero, and I suspect that short trips in extended cold might be a corner case in Mazda's view and not something they tested for. Severe use according to the owner's guide - absolutely. But 4.8% dilution after 800 miles?

Jim

 

[901Memphis]

Wear looks pretty good for breaking in. Fuel dilution shouldn't be a concern if wear is good.

Consider sending your sample to a lab that does actual checks for fuel dilution and doesn't just estimate based on Flashpoint.

 

[Quattro Pete]

Originally Posted By: jwagner
Given the strong gas smell of the oil, I'm surprised it's as low as 5%.

Don't get hung up on this too much. It takes very little gas for the oil to start smelling like gas. I had numerous cases where my oil reeked of gasoline, yet fuel content was minimal.

Agreed with other poster to send a sample to a lab that actually does gas chromatography test to determine fuel content accurately.

 

[rshaw125]

Originally Posted By: SF0059
Was the car highway driven for 20 minutes per Blackstone's instructions?


Important question. I see little point in sending a sample to Blackstone unless the vehicle was run on the highway for 20+ minutes just before sampling. I personally think 20 minutes is a bare minimum. 45 minutes would be ideal. Then sample right away.

 

[jwagner]

Originally Posted By: 901Memphis

Consider sending your sample to a lab that does actual checks for fuel dilution and doesn't just estimate based on Flashpoint.

Where can I find such a lab? Google isn't helping.
thanks,
Jim

 

[Quattro Pete]

Polaris, I think.

 

[badtlc]

From my own testing, I highly advise running premium (91+ octane) and see if your fuel dilution disappears like it did for me.

Good luck.

 

[badtlc]

Originally Posted By: Eddie
This is the first Mazda SkyActiv engine UOA that I have seen with a fuel dilution issue. Sounds like a stuck open injector or something else is wrong for sure. The wear values don't look bad for an engine that is not broken-in yet. Ask Blackstone to repeat the analysis, incase something in the lab got messed up. Ed


Um, every skyactiv UOA but one has had fuel dilution issues.