jrc903

I purchased this vehicle about one month ago. 114200 miles when i got it.
Since then I have driven about 800 miles. In general the vehicle runs fairly well. In fact, my only complaint (and it is a large one) is that the car appears to be eating oil at such a fantastic rate that it should not even start. But start it does-with ease. It does not smoke--even under hard acceleration.

What I have learned about the engine.

1. Compression on all four cylinders is about 215 psi +/- 5 pounds (both cold and warm)
2. Compression on all four cylinder raises about 14.5 percent when equal amounts of oil is added to each cylinder.(rings appear to be good in all cylinders)

3. Spark plugs for 3 or the four cylinders show normal to slightly hot operation
4. Spark plug for number 2 shows slightly darker color...
5. Spark plug for number 2 when first changed- shows oil scoot building up on only one side of plug. Direct observation is that oil scoot builds up on grounded side of plug.
6. Exhaust pipe shows oil scoot.
7. Oil level does not (always) return to same level even after just doing simple compression tests.
8. Oil level varies.. sometimes 50 mile trip shows no oil use. other times it shows 1 quart down
8.1 Oil not NOT leaking out of the engine (at least not while it is parked)
8.2 That after putting at least four quarts of extra oil in this engine--- nothing is reaching the ground.. a careful look at the outside of engine shows it almost factory like clean.. very strange..
9. Oil pan drained and refilled with exactly 4.5 quarts.. shows correct level on stick.
10 PCV value was found to be stuck--- replaced on day two of ownership.
11. Inside Cam cover--shows no sludge buildup. but oil in crankcase indicates a sludge problem from previous owners neglect.
12. Engine treated with Sea-form twice
13. Oil is getting cleaner with every change but not clean yet
14 Interdependent mechanic looked at engine. but was similarly mystified as to the source of the oil loss. Tends to believe that value guide seals may need to be replaced but is not convinced that that can explain why oil appears to just disappear from crankcase--without leaving more than the trace it does. Bad seals on number 2 might explain the level of carbon buildup without blue smoke but nothing explain why sometimes the engine appears down 1 quart after only 62 miles of operation. Said that crankcase pressure at the oil filter hole seemed high.. Said he checked PCV system operation and found it working correctly. Said he was going to go on his trade forums to see if there was any service information from Honda on missing oil.. etc etc.

At any rate, I am at wits end on this engine.. Somehow I get the impression that it may not be as bad is it appears--but can find no reason to say WHY I think that? While the car looks like brand new-- (from 10 feet away) I can not drive it with any confidence-- therefore can not drive it... I need to drive it..

Any input on this strange situation would be most appreciated.

chikin pickle

Check your coolant level. Some F23 blocks have a casting defect, allows oil passages to leak into the water jacket.

jrc903

I am pretty sure that the coolant remains clean. But with porous engine block possiblity, this is the first thing I considered. I will, however reexamine this issue.

phootbag

When piston rings wear you usually get smoke during heavy acceleration or all the time. When valve seals leak you usually get more smoke when decelerating due to the higher engine vacuum.

It is normal to have some pressure in the valve cover. All piston rings leak to some extent. If the number 2 spark plug was considerably more contaminated than the rest it is an indication there is an issue with that cylinder. If you're gaining 30 psi after "wetting" the cylinders with oil there is a possibility the cylinder walls have SOME scoring or the rings are leaking a bit. But, like I said, all rings leak. 30 psi increase isn't all that much.

Bottom line, if you're losing oil and it isn't leaking externally, it's leaking internally. Most likely going out the tailpipe.

jrc903

By visual observation, cylinder number two is burning some amount of
oil. The other three are not. This tends to rule out anything that
could be in common to all four cylinders--like PCV etc. Having said
that, I can find no measurable difference in compression between the
four cylinders: cold/hot, dry/wet. During the wet compression test, I
am getting a 15 percent increase in all cylinders. This is not only
consistent but it is within what one would expect to see if rings were
in good shape anyway. 30 psi against 220 psi is about that.

To do the wet test, I injected a small amount of oil in each cylinder.
One of the offshoots of this was to find out exactly what the car would
do with this oil. Not surprisingly,, it smoked like a chimney for a few
minutes. Showing that if a lot of oil is injected into the combustion process, the cat converter will NOT make it disappear. That amount of oil for all cylinders was perhaps about 1/10 of
a quart of oil. Contrast that with "apparently" losing 1 quart in 60
miles without any trace) As I have said-- i Do get oil scoot in the
pipe each time i drive it so it is clearly burning SOME oil-- and I
suspect it is getting it from number 2 through one of the value guides.
However, that does not explain why every time I crank over this engine
after having first adjusted the oil level to be correct-- the oil level
fails to return to the original level---- even after several hours.

Clearly, all that oil is NOT going out the tail pipe (because in some
cases the engine has not even been started)---but it is just not coming back
to the oil pan. This leads me to wonder how much total oil
eventually gets into the engine? According to AMSOIL website,, one of
the 40 reasons for oil consumption is a combination of plugged oil
return passageways and the owner adding oil to an engine that APPEARS to low---but in fact has trapped oil somewhere making it only appear the
level is the pan is low. And thus over pressurizing the oil system and
THEN blowing out value guide seals.

IF the coolant was not bright green but murky, the game would be over.
and I would be screwed. But as far as i can see,, not off coloration or volume increase in the cooling system. No oil floating on top of the coolant etc.

phootbag

There are multiple oil return passages in the head and block. They are about the size of your pinky or ring finger. I think it would be strange for them to plug up. If you are wondering if the oil return passages are restricting the oil flow back into the engine you could remove the valve cover after you confirm the oil is low on the stick. If the top of the head is full of oil you know where it's going. If the oil weren't returning to the oil pan I'm sure at some point the oil level would get low enough for the pump to suck air and cause the oil light to come on.

There is only so much room for extra oil to go and not show up on the dipstick. If it's not getting trapped above the head, or going into the cooling system it is probably getting burned.

Have you ruled out someone playing tricks on you?

AccordVT

I'm thinking this has something to do with the oil filter, oil pump and/or stuck oil control rings on your #2 cylinder.

So your saying that you do an oil change, drain the pan and replace the filter, put 4.5 qts in it, start it, shut it off, and then the oil level is what?
Assuming it's at the correct level from there, you drive it 50 miles and it shows no oil loss? Then you drive it again and it shows a quart down?
How much oil is the car using? Your not being very clear at all.

jrc903

Thanks for the comments.

As I have said, number 2 cylinder is eating some oil--I think via value guide seals. However, the car runs reasonably well. It does NOT smoke, it does not throw CEL codes related to the engine. The tailpipe gets black with scoot. I can not for the life of me find any external leakage. Keep in mind that eventually number 2 plug becomes dark with slight oil scoot. It does not become wet with oil. It does not appear to misfire from fouling. So--- the reason I don't drive this car much is---- the notion that after draining the crankcase/oil pan, changing the filter(the last time), refilling it with exactly the specified amount of oil, driving it 62 mile.. the oil level shows least 2/3 of a quart low after it is parked several hours. So--yes-- the obvious conclusion would be: that it is burning the oil through the combustion process.

Now some will say that an "engine" with this much going for it could consume this much oil, never skip, never throw CELs, go like hell, and NOT ever smoke. I presume they would also say that the catalytic converter must so good(not for long-- however), that it burns up the smoke smoke before it can leave the vehicle--just leaves solid residue in the form of scoot. IF that is correct, then why does the following happen: I inject a small amount of oil into each cylinder(totaling not more than 1/10 of a quart) for the wet compression test. Then start the engine.. car smokes like a chimney for quite a while. Surety, if the Cat converter can burn up 2/3 of a quart of oil-- it can easily take care of 1/10 of a quart.

As far as someone fooling me.. well besides the dealer that sold this car to be--- the only possible person that could be fooling me.. is ME. I have retraced my steps on this thing several times. Yesterday, i pulled the value cover again to see what oil was hanging around. I found one pocket of oil over in the left front region. I even used a piece of flexible installed 14 gauge wire to probe down the oil holes to the crankcase. I added oil to see how quickly it ended up on the the dip stick. The oil is not being trapped up there..

One thing that I have failed to mention. Because of the way the car looked, drove, etc. I did a stupid thing in not looking at the oil stick before I signed on the dotted line. When I got it home, I found the oil was black,, the oil filter was oversize, but screwed on so tight I finally had to have a mechanistic in the next town replace it for me. (before I got the filter off,,i changed the oil twice-trying to clean up the engine-- now with the new filter it it is beginning to come around) I think it is now likely that the original filter was being bypassed due to sludge formation etc. Now the filter is back on and very tight---but is still not the correct size for that car--too small. Given how hard it is turned on--- i wonder what that is about with both of these filters. SO that comment about OIL PUMP/Filter may be relevant.

So that is about all I can add to the discussion at this time. I am NOT making any assumptions about this engine. So--- fire away...

phootbag

If the oil galleys are clear and the oil is disappearing but not leaking externally the oil is getting burned. Just because there is no smoke doesn't mean the oil isn't getting burned. Burning 2/3 quart in 60 miles is different than burning 1/10 quart at start-up. Know what I'm sayin?