Oil is too full... what the heck!?

Went on a big road trip with the car.

She had been burning a bit of oil on the trip and we added as we went (nothing new) however at the very end of the big trip, she threw a CEL.

P0304...

she wasn't running bad, oil looked good... so I told my wife to go ahead and drive it and I would clear the code the next day, and we would see if it came back.

Today she tells me it's running rough, sure enough it was.

When I checked again, both p0304 AND p0303. So... CRAP!

I check the oil, and it looks OVER filled... so I think well crap, maybe I added way too much oil and it wasn't burning like I thought.

So I changed the oil, and cleared the code... took it around the block (she always runs a bit rough at first after unhooking the battery... so she was rough... no big deal.

But when I check the oil again... once agian I CAN"T TELL how much oil is in there b/c it's WAY above full.

All I can think is head gasket leaking fluid into the oil... thoughts? It still seems to be running rough but not overheating. No CEL again yet... but my guess is it is coming.

What would cause the dip stick/oil to show WAY too full like that? I'm not sure WHAT the dip stick "dips" into to check it.

Any suggestions/help is appreciated.

The dip stick enters the pan at a very odd angle. Depending on when you're checking it (temp of engine and how quickly after shutoff) it can vary greatly.

What were your checking conditions? Did you wait at all after shutdown to check?

My first oil change with this car I over filled because I checked the oil right after I turned the car off. It needs some time to let oil drain back into the pan before checking. I'd give it maybe 30 minutes to be safe. Also I think you need to be sure to check the side of the dipstick with the text. In my experience, somehow looking at the back side of the dipstick always showed more than the front side.

Now, you probably know that, so with that being said, is it possible the dipstick in your car is from another model Subaru? Maybe a long shot, and even if it is it might not matter.

How did the oil look when you drained it? Should be pretty watery if coolant was getting through the head gasket. And I'd expect to seem some oil in the coolant. How's the coolant level?

And if coolant were to be getting into the crankcase, obviously the coolant level in the radiator would be low.

So is the radiator and tank above the turbo full?

I check my oil by opening the hood, pulling the dip stick about 3-4" and close the hood, after work, (8 hours later) pull the stick wipe it with the rag I keep tucked by the battery, then check the oil level. read both sides of the stick.

The car must be on level ground.

If you wait over night, (same process) you can get a good reading too.

Next question, how many miles on the car ?

Is it on the stock tune ? Oh, I see stage 2.

How long has it been off the stock tune ?

Drain oil and determine if there is coolant in your oil. But if you were leaking that much coolant you'd have coolant level issues too.

and milky colored oil.

okay... so, the p0304 came back today. no p0303 yet.

The oil LOOKS like oil... and when I drained the old Oil there was nothing odd colored about it... looked like oil.

The oil in there now is pretty light in color b/c it's brand new, but still looks like oil.

I'm getting ready to head to lunch so I'm going to check it again. Guess I'll need to take it to the shop about the P0303 & P0304 issues... I was doing some forum reading on here, and looks like those can be due to about anything.

To answer everyone's questions.

1) I added about 4 and a pinch under 1/2 quarts (which is what I typically add, and keep the rest in my car for top offs)

2) ~120,000 miles... been running stage 2 tune since ~90,000 miles when the turbo blew and replaced with new.

3) When I checked the oil it was on a SLIGHT backwards decline (if anything I'd expect it to check low) I did check shortly after (almost immediately after) turning off the car... so again, I would expect it to check low.

4) coolent level looks good... not overheating.

Is there a COMMON cause for P030X codes? are the 3&4 on the same side of the car? I.e. could I have some fuel issue on that rail that might cause those codes? Bad gas (I was filling up in other states where I have no CLUE of the quality). I'm just not sure how to troubleshoot this... and at what point and time the car SHOULDN'T be driven to avoid serious damage.

cylinders 1 & 3 are the passenger side (bank1) 2 & 4 are the drivers side (bank2)

When it comes time, O2 sensors, front is bank 1 rear is bank2

your codes are either coils or fuel injectors. The normal is to swap them around an with a good one and see if the code follows it.

Do injectors first, easier.

Your oil sounds ok, a little over is not bad.

I check my oil by opening the hood, pulling the dip stick about 3-4" and close the hood, after work, (8 hours later) pull the stick wipe it with the rag I keep tucked by the battery, then check the oil level. read both sides of the stick.

 

The car must be on level ground.

 

If you wait over night, (same process) you can get a good reading too.

Since the process for checking oil on these cars is always a topic for discussion, I'll second this process. I let the car sit over night and find my readings are much more consistent.

Since the process for checking oil on these cars is always a topic for discussion, I'll second this process. I let the car sit over night and find my readings are much more consistent.

It's because the oil is slow to drain from the heads on these boxer motors.