Dip stick shows no oil level on first removal, reinsert it and level is fine. What’s up with that?

Joined
Dec 7, 2021
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So every time I first check the oil level in my wife’s Mercedes, when I pull the dip stick it shows zero oil. Absolutely dry dip stick like it is a few quarts low. I reinsert it and count to ten and pull it and it now shows oil, actually sometimes too much oil but it is serviced at the MB dealer and I assume they put in the right stuff and amount. The top of the dip stick where you grab it has a nice “O” ring on the part that goes in the tube. Tight seal at the top.

I’m trying to figure out what causes what I observe and have come to the conclusion that the tube the dip stick rides in goes well into the oil pan and when the car is operating, the oil level is below the tube end. The dip stick does not stick out past the end of the tube. When you shut off the engine, the oil returns to the pan but it can’t come up the dip stick tube because of the tight seal and the other end. Removing the dip stick allows the oil to flow up the tube so a second attempt works. Does this sound right?

Any other cars out there with this peculiar oil level check feature?
 
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Dec 24, 2014
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My Transit connect does this. I guess there is a vacuum that pulls the oil out of the dipstic. On first pull its totally clean, reinsert and oil level is normal. Idk. Scared me the first few times I saw it.
 
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My 2004 Mazda 3 2.0 did that if you pulled it first thing in the morning . It almost gave me a heart attack the first time. I don't know how it's possible for something to be sticking down into a pan full of oil and come out dry, but it happened every time.
 
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I think it's because the dipstick tube is sealed tightly at the top, so it won't let vapors escape. Of course when the engine is running any oil inside the tube will travel into the pan but when the engine is shut off, the captured air won't let the oil run back up into the tube untill that trapped air is released.
My Mercedes does this too.
 
Joined
Dec 24, 2014
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This is just another mystery of the universe along the lines of, does the light in the refrigerator go out when you close the door, or how many licks does it take to get to the center of a tootsie pop.
3 according to the impatient owl. Or more

 
Joined
Apr 19, 2014
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So every time I first check the oil level in my wife’s Mercedes, when I pull the dip stick it shows zero oil. Absolutely dry dip stick like it is a few quarts low. I reinsert it and count to ten and pull it and it now shows oil, actually sometimes too much oil but it is serviced at the MB dealer and I assume they put in the right stuff and amount. The top of the dip stick where you grab it has a nice “O” ring on the part that goes in the tube. Tight seal at the top.

I’m trying to figure out what causes what I observe and have come to the conclusion that the tube the dip stick rides in goes well into the oil pan and when the car is operating, the oil level is below the tube end. The dip stick does not stick out past the end of the tube. When you shut off the engine, the oil returns to the pan but it can’t come up the dip stick tube because of the tight seal and the other end. Removing the dip stick allows the oil to flow up the tube so a second attempt works. Does this sound right?

Any other cars out there with this peculiar oil level check feature?
Here's your answer. I had the same question. The bottom of the dipstick is almost touching the bottom of the oil pan. This is done so the dealers can vacuum out the old oil. This is the preferred way to change the oil. They have a rubber fitting that fits the top of the oil tube to suck the oil out. Of course they don't tell anybody this. It is so easy to change the oil/filter on these cars that you should do it your self. I don't know what the dealers charge for an oil change, but whatever it is, they are making a killing. No need to lift the car or take off all those panels.
 
Joined
Apr 19, 2014
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Here's your answer. I had the same question. The bottom of the dipstick is almost touching the bottom of the oil pan. This is done so the dealers can vacuum out the old oil. This is the preferred way to change the oil. They have a rubber fitting that fits the top of the oil tube to suck the oil out. Of course they don't tell anybody this. It is so easy to change the oil/filter on these cars that you should do it your self. I don't know what the dealers charge for an oil change, but whatever it is, they are making a killing. No need to lift the car or take off all those panels.
Get yourself a Mityvac for about $80. One of the rubber stoppers they give you fits the oil tube. You can even buy a special fitting for the oil tube. Loosen the oil filter cap a few turns and let it drain the oil for a couple of minutes. Then take it off and put the new filter in...it will only go one way. The only thing you have to be careful about is make sure to replace ALL the oil rings. Screw the filter cap back on hand tight...that's all.
 
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I use the Mityvac on both my cars, both of which conveniently have cartridge filters sitting on top. Its actually a pleasure to change oil/filters now. :)
 
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Buy a Tesla...
I use Supertech in mine.

1641150571818.jpg
 
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Michigan
or how about the 2az-fe engine in my scion tC?? When you first change the oil, pour the oil in, check the dipstick.. ZERO registers on the dipstick. Wait.. then wait again.. wait.. all of a sudden more and more appears on the dipstick, this is after the engine was run. Once it's to the full level then magically it's always at that level.. Maybe the oil went through the domain where all the socks from the dryer go when they disappear!! 🤪
 
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