LexusGXFan

I use OBD Fusion to track my engine oil temp, coolant temp, and AT Temps.

With the colder temps, in the teens to 30s, my Engine Oil Temps runs 185F when the engine has been running for over an hour.

At this temp of 185F, how long does it take for the small amount of fuel present in the engine oil to be burned off ? I know that colder weather produce more fuel in the oil, but didn't know how long an engine needs to up to operating temp before the water and fuel are burned off.

Thanks !!!

william489

I have this ( ), I will have 20F tomorrow moring, I can check if my odb 2 reader can tell me what I have.

downshift1

The amount of fuel dilution is almost immeasurable due to emissions standards requiring a limited amount of crank case pressure (blow-by).

Once the truck is up to operating temp you've already burned it off.

ASE

I guess physics has changed since the EPA said so ??? So this means that Honda customers were imagining the fuel dilution issue on the 1.5 L Turbo engine ... so the Class Action law suit against Honda can go away now.

LexusGXFan

Downshift,

I respectfully disagree with your comments on fuel dilution. You will have fuel dilution issues in the 4.6L engine IF you continually have short trips, etc...

The reason I asked this question is because I did have fuel show up in my UOA for both of my GXs. This is because I didn't let the engine reach operating temp before draining the oil out.

So, that is the reason I posted this question.

ASE

The oil temperature does not have to reach the boiling point of water for any condensation build-up in the crankcase to evaporate (or fuel for that matter) ... it will just take a little longer. I would assume that 185-degrees for one hour should be sufficient. Only if your oil really smells like gasoline, you have reason for concern.

So unless you have a high-mile engine that has significant blow-by, and constantly drive short distances where the oil does not reach operating temperature for very long ... you have nothing to worry about.

Now the recent Honda 1.5L Turbo is another story Honda should be ashamed and deserves to lose a generation of customers for eternity.

LexusGXFan

I just had a higher reading (1.4%) of fuel in my last UOA with a slight viscosity drop. It's on me because I didn't drive the GX long enough.

No smell of fuel.

Just curious how long it took to get rid of the water and fuel.

Yes, Honda did a terrible job on the 1.5L engine.

downshift1

There are always engine design failures (1ZZ/EJ257/L15B7) but they aren't the norm.

The P0128 CEL will set after ~15 minutes of driving if you don't reach the specified temp unless IAT is seen to be of a lower value than average.

Yes if you drive less than 15 minutes on a consistent basis you will see higher than average fuel dilution and probably accelerated wear in a lot of components.

If you drain the oil when it's not warmed up all the way you will see fuel dilution.

LexusGXFan

Downshift,

Lets say you have 4 short trips (less than 5 miles total for each trip) in 7 days and then on the 8th day you have a trip for 40 minutes at highway speeds. Will the fuel get burned off during that trip ??

downshift1

Theoretically It should.
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