TGDI, Early OCI and Fuel Dilution

[Gene K]

I'm starting to rethink the rational for early OCI for TGDI. The F150 2.7EB and 3.5EB I've seen with good trending of UOA have no real correlation with Fuel Dilution and Interval. A 2,000 mi sample is just as likely to have a low flashpoint or high fuel as a 10,000 mi samples. Also while anecdotal both of the 400,000 mi Ecoboost I'm familiar with have higher mileage OCI (In the 20-0% of IOLM Range).

So my question is if fuel dilution is a constant assuming the oil holds up to the dilution what are we accomplishing with the early OCI? Would basing the change on things like iron ppm per 1000 mi (ie traditional standards) make more sense?

 

[MCompact]

The GDI turbo in my 2007 Mazdaspeed 3 had an evil reputation for high fuel dilution levels. If you read the Mazdaspeed boards the common wisdom was that 3,000 mile OCI- and that Mobil 1 was absolutely terrible oil. I bought one new and repeated UOAs showed that a 7,500 mile OCI with M1 5W-30 was conservative, if anything.

 

[4WD]

Originally Posted by Gene K

So my question is if fuel dilution is a constant assuming the oil holds up to the dilution what are we accomplishing with the early OCI? Would basing the change on things like iron ppm per 1000 mi (ie traditional standards) make more sense?


Difficult and expensive to measure … If fuel diluted oil is a problem with a certain engine … perhaps a Fumoto valve and a fresh quart of spike oil (2/3 of OCI) is a quick and easy boost.

 

[JohnnyJohnson]

Fuel Dilution is a manufacturer problem they have push off on customers.

 

[4WD]

Originally Posted by JohnnyJohnson
Fuel Dilution is a manufacturer problem they have push off on customers.


And a big pain for oil formulators trying to offer extended range oils that can deal with most other issues.

 

[Gene K]

Originally Posted by JohnnyJohnson
Fuel Dilution is a manufacturer problem they have push off on customers.


But if the engine lives 400,000 mi on 10,000 mi oci how much of a problem is the fuel dilution?

 

[user52165]

Originally Posted by Gene K
Originally Posted by JohnnyJohnson
Fuel Dilution is a manufacturer problem they have push off on customers.


But if the engine lives 400,000 mi on 10,000 mi oci how much of a problem is the fuel dilution?


How many top offs would be required?

 

[Mainia]

Fuel dilution below 6-7 % is really nothing to worry about. I have tracked mine for 20,000 and I don't have wear. In the winter I dump at 3,000. People get all up in their head and freak. The ones who test and see it is not an issue, don't worry about it after they test 5 times and find it is nothing to worry about if there is no wear.

 

[LotI]

How do you know the wear? A UOA will tell the condition of the lubricant, not the donor vehicle(hence the term oil analysis). Wear would require a tear down of the motor.

 

[Mainia]

Originally Posted by LotI
How do you know the wear? A UOA will tell the condition of the lubricant, not the donor vehicle(hence the term oil analysis). Wear would require a tear down of the motor.


It's a Hyundai, we look for piston skirts and chunks of bearing in our oil changes, how about you?

 

[SWS]

That is an honest question, Gene K.
My own thinking - mainly after following the issues in the Honda 1.5T engine in the CRV (I was interested in buying one):
-> I buy new vehicles for the long term, 20 years.
Tennessee climate & low road salt supports this -
2 of my vehicles made it 20 years / 200K miles in TN.
-> My driving has a lot of short-trip, in-town driving.
As I understand it, this is the worst-case for fuel dilution.
-> There are some engines in which actual damage has
occurred to rather new engines & blamed on fuel dilution.
However, I do not know of anyone that has an
authoritative summary of which are tolerant and which
are harmed by fuel dilution. Indeed, the damage, if any,
could take 10 years to appear.
-> I remember the old days of huge cast iron V-8 engines
with carbs warming-up in the winter in Ohio.
A lot of fuel dilution reported and I saw oil drains
as thin as water, completely black, and smelled like fuel
after 3 months. This is a personal negative impression
only - I have no data on engine longevity vs a similar
engine in a warm climate from those days.
-> My personal opinion is that gasoline in oil is always of
concern and is harmful to "some" degree for a short-trip
driver like me.
This influences which new vehicle I buy for the long term.
Rejected the CRV specifically and all Turbos in general
for this reason - not worth the worry-factor to me.

 

[bbhero]

Originally Posted by Gene K
Originally Posted by JohnnyJohnson
Fuel Dilution is a manufacturer problem they have push off on customers.


But if the engine lives 400,000 mi on 10,000 mi oci how much of a problem is the fuel dilution?



And I'd bet no one has done that on a 2015 or 2016 or newer vehicle.... Or if one random donkey person did it... They are a huge outlier...

Candidly in my circumstance with a 312,000 mile car with a CVT... I'm quite likely... A pretty huge outlier myself....

 

[CT8]

Is soot is a concern?

 

[bbhero]

Originally Posted by CT8
Is soot is a concern?



Great point CT8 ^^^^^^^

That is thought to be part of what leads to timing chain wear.

 

[dudemancool1904]

Ahh remember the forum wars? brotella Vs PUP. Hahah

Originally Posted by MCompact
The GDI turbo in my 2007 Mazdaspeed 3 had an evil reputation for high fuel dilution levels. If you read the Mazdaspeed boards the common wisdom was that 3,000 mile OCI- and that Mobil 1 was absolutely terrible oil. I bought one new and repeated UOAs showed that a 7,500 mile OCI with M1 5W-30 was conservative, if anything.

 

[Mainia]

Originally Posted by CT8
Is soot is a concern?


Yes, but at a 3,000 mile dump it is minimal.

 

[Triple_Se7en]

(for lifetime vehicle owners)
Concern over buildup to the pistons and valves via carbon / soot, is why I choose 4k OCIs with my 2019 GDI. My Wife's 2020 MPI engine goes longer OCIs.

Ford designs are probably the best ones, to combat after-effects of their GDI / TGDI engines. Toyota would be another make that leaves cleaner trails.

Anyone that wants to run 10-15-20k OCIs, they have the free will to do so. If you sell the vehicle prematurely, then just run anything that meets the specs, for as long as you like.

 

[Mainia]

Originally Posted by SWS
That is an honest question, Gene K.
My own thinking - mainly after following the issues in the Honda 1.5T engine in the CRV (I was interested in buying one):
-> I buy new vehicles for the long term, 20 years.
Tennessee climate & low road salt supports this -
2 of my vehicles made it 20 years / 200K miles in TN.
-> My driving has a lot of short-trip, in-town driving.
As I understand it, this is the worst-case for fuel dilution.
-> There are some engines in which actual damage has
occurred to rather new engines & blamed on fuel dilution.
However, I do not know of anyone that has an
authoritative summary of which are tolerant and which
are harmed by fuel dilution. Indeed, the damage, if any,
could take 10 years to appear.
-> I remember the old days of huge cast iron V-8 engines
with carbs warming-up in the winter in Ohio.
A lot of fuel dilution reported and I saw oil drains
as thin as water, completely black, and smelled like fuel
after 3 months. This is a personal negative impression
only - I have no data on engine longevity vs a similar
engine in a warm climate from those days.
-> My personal opinion is that gasoline in oil is always of
concern and is harmful to "some" degree for a short-trip
driver like me.
This influences which new vehicle I buy for the long term.
Rejected the CRV specifically and all Turbos in general
for this reason - not worth the worry-factor to me.



Hyundai 1.6T are as bad as the Honda 1.5T. When I bought my car I had a 10 pack of oil testing bottles pre bought before I even received my car. I knew what I was getting into.

I have ran many different oils. My long term choice has been Mobil 1 ESP 5w-30. The lowest limit I will go on ANY oil is a 11.0@100C and a HTHS 3.5. NO WAY I would every run a 5w-20 oil in my turbo car. Even in the summer I gained 3/8 of a qt by 500 miles. I just switched out to a first run of Redline Euro 5w-30, and my jaw has dropped since the first time in many oil changes my oil is dead solid on the the dot where it was when I filled it. 600 miles later. I should have 3/8 of a qt more oil as I have with many top oils. The Ester must be sealing better even though the GDI injectors must be washing the other oils off the cylinder walls. That's the only thing that it could be. I can't wait to see my 1,000 mile and 2,000 mile mark to see if am still dead on the dot. No oil has not gained fuel in this car.

 

[Mainia]

Originally Posted by Triple_Se7en
(for lifetime vehicle owners)
Concern over buildup to the pistons and valves via carbon / soot, is why I choose 4k OCIs with my 2019 GDI. My Wife's 2020 MPI engine goes longer OCIs.

Ford designs are probably the best ones, to combat after-effects of their GDI / TGDI engines. Toyota would be another make that leaves cleaner trails.

Anyone that wants to run 10-15-20k OCIs, they have the free will to do so. If you sell the vehicle prematurely, then just run anything that meets the specs, for as long as you like.


I am running our Ford Connect delivery van with Mobil1 5w-30 Extended at 15,000 mile dumps with an Ultra and it has good UOA's from the second oil change. I dumped at 2,500 miles. 150,000 miles and counting. Nice and clean valve train when we stick a camera in the valve cover. MPI is so nice when it comes to oil changes. It has had 3 trans 100% dumps in it life time too. First trans dump was at 25,000 miles to get all the break-in out.

 

[MCompact]

Originally Posted by JohnnyJohnson
Fuel Dilution is a manufacturer problem they have push off on customers.


I flipped my MS3 at 158K miles and performance(based on in-gear acceleration times) was the same as it was at 50K miles- and the UOAs were likewise as good or better than the UOAs from @50K miles.
Some manufacturer problem- a problem so terrible I now have two GDI turbos.
It's a wonder I'm able to sleep at night...