I recently purchased a great looking and riding Accord with 114K. Everything about his car is great except that it appears to be using quite a bit of oil.

Here are the particulars:

Whats been done:
5W30 oil
Replaced stuck PCV
Replaced Spark Plugs
Sea form treated oil and gas

THE GOOD NEWS:
Spark plugs look normal--appear to be running about the right fuel/air mixture--dry.. no oil present on center post or electrode.
Car starts and runs great.. no hesitation, no skipping, no CELs.
Car feels very strong in both acceleration and near top end
NO exhaust smoke ever.
Car gets good fuel mileage--over 25 mpg
No oil contamination in coolant


THE BAD NEWS:
Oil is disappearing at a rapid rate--Loss rate greater than 400 miles/quart
Exhaust pipe is coated with black scoot.

Question: Is there any know reason for this other then bad oil rings? Even if it is the rings--- at this rate of loss I would expect the plugs to almost be oil fouled--instead of normal. Any suggestions would be appreciated. Rebuild/ReplaceEngine/Trade Cars etc



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Honda
Accord EX
2.3L Vtech
114800


Engine Compression:215 psi across the board (tested both hot and cold)
New plugs
New plug wires
PCV replaced and system checked for proper operation.
Oil and oil filer changed.



Performance:
No Check Engine Light
Overall Good performance—but sometimes shows slight hesitation at about 3000 RPM
Gas Mileage: 25 MPG
No visible smoke
No oil on ground.. very clean bottom of engine.. (may have been washed by dealer)


Oil Consumption Test:
1.Emptied crankcase—left newly installed filter in place
2.Added exactly four quarts of 10W30 advanced auto brand oil—added 3 ounces of sea form.
Dip stick showed oil level exactly at the top mark on level floor- oil fill cap was level as well.
3.Cleaned exhaust pipe.
Drove 65 miles—maintaining 3000 RPMs with gear box
Car ran quite well in semi-heavy wind.. quite smooth at over 3000 rpms
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https://picasaweb.google.com/HondaMa...91449024346258
left to right 4,3,2,1

RESULTS:
Oil Level showed it down exactly one quart
Removed plugs..


(left to right... number 4, 3, 2, 1)

#1 showed slightly hot
#2 showed dark brown combustion—but with black scoot on outer electrode
#3 showed normal
#4 showed normal electrode color –but black scoot around outside

Exhaust pipe showed black scoot.
CONCLUSION:

Clearly burning LOTS of oil..
(However) No smoking, No leaking, no plug fouling, no engine missing, no major problems, no CELs


QUESTION:

1. Is it likely, that an engine that runs this well.. (very strong) does not show visible blue smoke . has more than enough,and even compression.. need rings? or could it be something else.. like value guide seals or something to with oil passageways or pcv system (despite being checked)


Update may 3 2011 9:25am est
I just performed another compression test.. however this time--- I decided to see exactly how much I could saturate the rings with oil (just in case they were not already saturated) and compare the results. One each of the four cyclinders, (for roughly the same amount of oil) I observed a 14 percent increase in compression.

Now--- while the picture of the spark plugs I had planned to include last time did not appear--- the plug from number 2 shows the most obvious affect from oil... the other three show white/brownish (close to stoichiometric ) After reading other posts the other day, regarding how leaking value guides/seals can cause oil to appear on the side of the electrotype corresponding to which (leaking) value is facing that side of the plug.. and sure enough-- plug 2 shows it coming from one side more than the other three sides.. don't know which of the four values is facing that plug.. but from what I read--it is most likely, one of the two exhaust values.

The thing that bothers the hell out of me, is how one cylinder could be eating that much oil without even a hint of trouble.. But rest assured-- after i got done injecting oil into those cylinders for this wet compression test-- it smoked on start up ALL RIGHT.. so again--the notion that the cat. converter is cleaning up all that oil... before it hits the end of the pipe--- is put to rest. So--- number two cylinder has something wrong with it regarding oil..(by plug color ect) but this may be a dual or triple type of a problem stemming from the same root cause....(bad car care on the part of the previous owner). because that oil is going somewhere and the car does not act like it is all going through the combustion cycle. BUT---I have not heard of a situation where the bottom of the engine suddenly opens up while the car is moving at 60 mph, drops oil on the ground.. then seals itself up clean, before it can run out of the garage floor.. but this problem is kinda that weird.. so.. i am open to any suggestion?At any rate, the notion that even while only number 2 cylinder shows oil impact--- that all cylinders could be blowing exactly the same compression both hot/cold dry/wet. kinda indicates that the problem with number 2 is not oil rings or rings period.. BUT then again.. I am only a layman on Honda engines.. So if anyone out there--- has any better ideas I would love to hear from them..

 

Make sure pcv is functioning correctly as this can pull oil excessively.

Also check your vacuum level under moderate acceleration. Tape a vacuum gauge to the windshield and rig to a vacuum source on throttle body. If pressure goes positive (vacuum is negative), crankcase fumes get pulled into the pcv air intake from crankcase. I had a Bronco that would do this pretty badly. Worn engine was problem. It ran just fine, but used a good bit of oil.

Is it leaking any oil? This much oil should be easily detected.

good luck

 

No leaking oil, the bottom of this engine is dryer than a bone. Othereise-- I would actually be quire relieved.

I had also considered the possibly that something other then the PCV value (the PCV value was stuck--but replaced) was causing oil rich crankcase mist to be pulled from crankcase. Because, if this oil was blowing by the rings it would be liquid.. and would certainly foul the plugs very quickly. I wonder if there is any easy way to disable the PCV system long enough to prove or disprove this theory?

 

If it's not leaking or in the cooling system, it's being consumed by engine. PCV can't legally be disabled as this vents crankcase vapor directly to atmosphere. If you PCV is clean, the scenario I described can pull vapor/oil directly into intake. The design of PCV limits function when vacuum level is low, but if pressure actually goes positive, then vapors get pushed into air intake. If this happens excessively, the oil consumption might be impacted.

It is possible to include an oil trap on both PCV intake and drain. These are widely available on ebay. Use of these would indicate excessive oil consumption by trapping the oil.

good luck

 

Well.. I will find some way to check the vacuum situation. However, with all the emission systems depending on good vacuum to satisfy the ECM, I wonder how far off it could be and not cause CEL indications and/or bad performance.

Here is another interesting observation. When I returned from my 100 mile test run yesterday, I pulled on to the concrete garage floor but left enough room to work in front of the car. The slab floor is basically level. I carefully adjusted the oil level back to the top mark. The car was then not restarted until about 10pm last night when I started the engine to move the car two feet forward to allow the door to close. This morning--- the oil level is showing down about one pint. My floor is dry-- no oil leaking.. yet starting the engine for all of 3 seconds.. caused this oil to disappear? It's "like" it is somehow getting trapped above the crankcase level--because it sure did not burn that in 3 seconds, and it did not end up on the floor. Any ideas about how this might tie in with the vacuum scenario?

 

That is strange about the oil level dropping after brief engine start up.

Keep trying to look for oil leaks around the car. Look for leaks around the timing belt cover, maybe where the engine and transmission meet up. Just thoroughly inspect to rule out leaks.

I would consider is having a compression test done on each cylinder to give you an idea if something is wrong with the engine. A leak-down test would give you a better idea of the condition of the compression rings. I am not sure if these tests can tell you the condition of the oil control rings.

 

Yes, I guess a compression or (leak down) test would be in order. I've got to get that (sea foamed) oil out of that engine tomorrow... going to change to heavier weight oil..and see how that goes. Once that is done-- I'm going to throw out every conclusion I've previously reached about oil consumption on this car and start anew.Then, see if I can make any sense of this car after that..

 

Valve stem seals can leak and cause oil burning. It seems to produce less smoke than oil bypassing rings. I had a Mitsubish V6 w/ leaking valve stems. It would run fine, and would not smoke at steady speed. However during a prolonged idle, it would begin to puff oil smoke regularly. On acceleration there would be a significant billow of smoke. Oil consumption was probably about 1qt/750-1000 miles.

good luck

 

Well.. the oil is still going out the pipe-- however, it does not "visibly" smoke on either start up or while running. As I said the other day, after the experience of seeing the oil level drop virtually before my eyes-- I was pleasantly surprised to see the oil level remain constant after a brief trip of semi-aggressive driving. But that optimism was short lived--as it turned out. Because, it does suck oil no doubt about that. Yesterday, I finally got around to doing a compression test and found that all four cylinders are running about 210-220 psi. The normal value is 178 psi. And so-- if anything, I have too much compression. I figure this might explain how marginal value guide seals may not be cutting it--but only when the engine is running. i.e bad value guide seals usually revel themselves when the car has sat turned off for a period of time.

Within the last hour, I treated the car with a dose of sea-form to the PCV intake line. While blowing out the sea-form, I got an engine check light--indicating a cylinder miss fire. Now---I have changed plugs and plug wires--so what else should I be concerned with to solve this intermittent CEL? At any rate, I am moving closer to finally going to the Honda dealer to see how their diagnostics compares with my "pre-established" tests/reality. But as someone said--value guide seals could be the problem--and coupled with high compression,,, that might even make more sense--don't know yet.. But if it is, that is not too hard to rectify. Because, I surely do not want to tear this engine down to do bottom end work. At any rate, I am open to any suggestions regarding this oil loss/compression/CEL questions.. Thank you.

 

After chugging that seafoam, you could clear any error codes that might have been caused by that. For your 1998, open the passenger door & get in the fusebox near the door hinges. Pull fuse #13 for a little while & then put it back in.