2009 Ford Focus, strange oil readings on dipstick?

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Howdy BITOG,

My daughter's car is a 2009 Focus (great car). One thing with this car however confuses me. If you let the car sit overnight, and then walk up and pull the stick it will generally read below the "safe" zone, over a quart low. Wipe it and put the stick right back in, and it will show correctly topped off on the next pull.

If I let it sit for a few minutes after running hot and check it then, it will also show correct levels.

I have always preferred to let check cars stone cold for what I considered the most accurate reading. I can't understand why it would show low when sitting especially when it doesn't show low if you put the stick right back in and check again without having started it.

Anybody seen this before? I have been going with the wipe and recheck reading but I don't want to be running it low if I am somehow missing something.
 
My 2011 does the same thing. I'm sure it has to do with the dipstick sealing and preventing oil from getting to the correct level in the dipstick tube.

I thought I had a real oil burner on my hands. Boy, was I surprised when I drained 7+ quarts out of the thing on the first oil change!
 
I always notice the level a little low, prob a quarter of a quart. But next pull is where it should be.
 
Originally Posted By: Miller88
My 2011 does the same thing. I'm sure it has to do with the dipstick sealing and preventing oil from getting to the correct level in the dipstick tube.


Probably this. Let it sit overnight with the o-rings outside the tube
 
Miller88 is right. Think of it like sticking an upside down cup under water. The water isn't able to reach the top (bottom) of the cup unless you burp it. I guess this also depends on the engine's design. Maybe you could test it by removing the dipsticks gasket?

If you are unsure of the level entirely, I recommend an oil change followed by a few checks. That way you know for sure.
 
Another way to think of it is sticking a straw into a glass of water but put your finger over the drinking spout of it. The straw won't have any water in it until you take your finger off the top of the straw.
 
I always pull and wipe the stick, then shove it back in for a second go before getting a read. Whether the car is cold or I stopped to get gas and check it then. Consistency is the key when measuring fluids. Either way, down a quarter quart is not a huge deal... if it was off the bottom of the stick after the second wipe, THEN you've really got problems...
 
As an experiment, after sitting overnight, yank out the dipstick 1"
for a few seconds and push back in, then pull for a reading and see if the 'upside down cup' theory
is true!
 
Just for a few days, slide the O-ring off the dipstick handle.

No, it won't be enough of an air leak to trip the CEL.

I'm think the seal on the O-ring is so good, it's messing with the levels of the oil in the tube.
 
Every late model motor I've had recommends checking the oil warm after giving it a few minutes drain time. The level when cold is never the same and probably not accurate. Noticed this first on my motorcycles with a sight glass.

Modern engines have smaller sumps and more oil remaining in the galleries. Also tighter tolerances mean less leak down. You need it hot and thin to measure accordingly.

The oil tube theory is wrong. Assuming perfect seal, air contracts as it cools and should suck the oil level higher up the tube.

What is probably happening is you're breaking a vacuum condition which is keeping oil up in the engine. Oil then drains out and indicates correct level. Try opening the oil fill and then take a reading when cold. It'll probably be correct.
 
Change the oil, put in exactly the specified amount, and see how the dipstick acts. That is your new normal.
 
Originally Posted By: DdDd
Every late model motor I've had recommends checking the oil warm after giving it a few minutes drain time. The level when cold is never the same and probably not accurate.


This does not appear to make sense. The level when cold is the level when cold, and accurate as such. The fact that it is inevitably different from the level when hot doesn't alter that fact.

It is, however, easier to be consistent with a cold measurement.


Originally Posted By: DdDd

The oil tube theory is wrong. Assuming perfect seal, air contracts as it cools and should suck the oil level higher up the tube.


Assuming perfect seal, air expands as it gets hot (engine on) and contracts as it cools (engine off) so you'd be back where you started.

IF it expands enough to blow bubbles when hot there'll be negative pressure in the tube when it cools, (assuming the end of the dipstick tube is below the sump level).This would draw oil up the tube and it'd over-read

IF the oil in the running engine is turbulent enough to contain air bubbles then these could add air to the dipstick tube and it'd under-read.

IF the oil-tube theory is correct, the problem would seem to be easily fixed by drilling a breather hole in it.
 
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Originally Posted By: KCJeep
Howdy BITOG,

My daughter's car is a 2009 Focus (great car). One thing with this car however confuses me. If you let the car sit overnight, and then walk up and pull the stick it will generally read below the "safe" zone, over a quart low. Wipe it and put the stick right back in, and it will show correctly topped off on the next pull.

If I let it sit for a few minutes after running hot and check it then, it will also show correct levels.

I have always preferred to let check cars stone cold for what I considered the most accurate reading. I can't understand why it would show low when sitting especially when it doesn't show low if you put the stick right back in and check again without having started it.

Anybody seen this before? I have been going with the wipe and recheck reading but I don't want to be running it low if I am somehow missing something.

The 2.3L on my dads escape (2008) does the same thing. First pull after sitting all night it shows low. Wipe it off and check it its normal.
 
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The first cold reading is correct. Oil migrates up the tube when you pull the stick so the second pull may show some of the tube oil and appear to be more full than the 1st pull.
 
Originally Posted By: Ducked

IF the oil-tube theory is correct, the problem would seem to be easily fixed by drilling a breather hole in it.


Just remove the O-ring. Done.
 
Originally Posted By: Linctex
Originally Posted By: Ducked

IF the oil-tube theory is correct, the problem would seem to be easily fixed by drilling a breather hole in it.


Just remove the O-ring. Done.


As a permanent fix? It'd suck in contaminants all the time.
 
I've seen this happen on ATF dipsticks, Volvo in particular.
Initial check and it's dry. 2nd time and it reads full.
 
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