Thought I would check the condition of my air filter and throttle body and I was surprised to find a shallow pool of engine oil when I opened the throttle plate and looked deep down. The throttle plate is actually clean and not sticking. I know what you're thinking..."he used 4 quarts of oil and overfilled"...nope. I used 3.5 quarts like recommended and when I checked the dipstick I was about a half inch below the full mark. Perfectly fine. I've always been cautions not to overfill and have always done my own oil changes. My 2008 has 86K miles. Question: How did this happen and how do I clean up that pool of oil? How do I prevent it from happening again? Where does the oil come in from? I ready this is a typical symptom of overfilling...this is why I'm confused. Can high speeds (70+ MPH) or high RPM cause this? I live VERY close to the highway (1/4 mile) and have to accelerate quickly on the entry ramp on the way to work while the engine is still cold.
Sounds like it might be blow by from over the years. Had a catch can in my Eclipse and caught a lot of oil in it. Maybe clean the PCV valve?
Don't worry about it. So many reports of this. Mine has been like that since I rolled out of the dealer new. Nothing your doing. Forget about it.
So, how to get the oil out. I placed some strips of paper towel down there, swished around with a screwdriver, and fished out with a long hemostat. Careful working around the throttle plate and MAF. You can remove two screws and get the MAF out of the way to avoid fouling it with oil. On the final swab I sprayed in a little carb cleaner and got it pretty clean. I recently replaced the PCV, which was quite a job. Haven't seen any new accumulations. My 2008 spends its entire life at highway speed. I think it may have something to do with the location of the PCV being on the side of the valve cover instead of the typical top venting location of other engines. Unless of course there are baffles on the inside that I don't know about.
Years ago I was told that B mode can be a cause. So long as you do not have a clogged PCV I do not think it is any concern.
Don't use paper towels that will leave debris behind. The best way to clean the TB is to rip an old t shirt in long 2 inch wide strips. Soak the strip a little with carb cleaner and stuff it down the TB with the butterfly cracked. Try not to use a screwdriver as it can nick the body wall. While the strip is shoved in there soak it with carb cleaner and wearing gloves use the strip and scrub it out the best you can. Remove strip and all the carb cleaner comes out with it. Try to get the edge and both sides of the butterfly. Repeat. This is just to clean the tb. The oil at the bottom is always there so don't bother cleaning it out it will come right back. Oil in the intake and fuel dilution in the oil is 2 of the weird issues with this motor.
Has anyone analyzed what accumulates down there? The paper towel strips that I very carefully removed, all in one piece mind you, had a distinct gasoline smell. Sort of a concentrated odor though, and the fluid did evaporate mostly but the strong odor remained. There was a little oil mixed in with it too. Maybe something to do with the slight regurgitation into the intake manifold of each cylinder charge during the compression stroke?
That's cause there's fuel in the oil. Smell the dipstick. And yes a human can smell 1% gasoline as gasoline is incredibly potent.