6th gen Accord, losing lots of oil, not sure where

[Joe]

2001 Honda Accord, 4 cylinder. I have to add oil regularly and I’ve been tracking this for a few years. I’m losing about 40oz per 1k miles. It seems to me that this is a LOT of oil, but I have no idea where it’s going. I’ve placed cardboard under the car a few times after driving it, and no drips.

So I figured it’s got be burning off, but to burn off that amount of oil would mean poor compression, correct? And poor compression would mean poor power and poor gas mileage, correct? Power seems good for a 4 cylinder Honda, and mileage is good. I get ~25mpg combined, and in the low 30s highway. Most recent long roadtrip, I got 34mpg (no air conditioning). I also don’t see blue smoke or smell burning oil. Would this kind of gas mileage rule out poor compression, or should I do a compression test?

As for leaks, one place where I noticed oil was on top of the transmission housing. This might be why I wasn’t seeing drips onto the floor – it was just falling off while the car was moving. That oil seemed to be coming from the distributor O-ring, which I replaced recently and oil is no longer leaking from there, but the oil loss continues.

Valve cover gasket seems ok and I don’t see obvious oil leak signs there (though I need to check the rear of the valve cover gasket a bit better).

I suppose a UV dye test is in order, but given the symptoms I’ve described (good power and fuel mileage, no drips when parked, large amount of oil loss, no blue smoke, replaced dissy O-ring), and that this is a 6th gen Accord, what/where is the most likely culprit here?

Topic

[David]

you are losing over a quart every 1k miles, but there are no drips or anything? I would expect wherever it’s coming out from to be a mess. The usual recommendation is clean things up, then look for where it’s coming from. A compression test and a leakdown test would be a good idea, if there are no obvious leaks. Has your PCV valve been replaced recently? Valve cover gaskets, cam/crank seals, and the oil pan seals are places to look, too.

[Richard Kirshy]

With that amount of oil loss your correct in assuming either burning it or leaking it.
Might suggest you start with a simple proper compression and leak down test on the engine.
If that shows no issue(s).
Then suggest you raise the car and support it properly and give the undercarriage a good inspection for oil.

[Joe]

[quote=”DrD” post=192445]you are losing over a quart every 1k miles, but there are no drips or anything?[/quote]Correct.

[quote=”DrD” post=192445]I would expect wherever it’s coming out from to be a mess.[/quote]So would I. There was a leak at the distributor o-ring (since replaced) and that didn’t drip to the ground, but onto the transmission housing. From there, it was being flung off the car while in motion. So that’s an example of how there could be a leak without a puddle under the car. Maybe something similar is happening with whatever leaks are remaining.

[quote=”DrD” post=192445] The usual recommendation is clean things up, then look for where it’s coming from. A compression test and a leakdown test would be a good idea, if there are no obvious leaks. Has your PCV valve been replaced recently? Valve cover gaskets, cam/crank seals, and the oil pan seals are places to look, too.[/quote]My friend has a compression tester, so I can perform that test. Though with the performance and fuel efficiency I’m getting (as good as EPA mileage rating for the car when new in 2001), and no blue smoke or smell of burning oil, I can’t imagine I’m losing a lot of oil via burn-off.

Yeah, I replaced the PCV valve a couple of years ago hoping it would resolve this issue. I’ll have to look more closely for leaks, but it’s not going to be the oil pan seal or any other seal that would drip oil directly onto the ground because that would have created an easy to spot puddle.

[Richard Kirshy]

One other item you can check is the oil pressure sensor / switch ( which every yours is equipped with )
If leaking, it would only happen while the engine is running.
So it is possible that it could leave no signs of dripping while the vehicle is parked.

[Mike]

To me, it sounds as if you are dealing with an oil consumption issue rather than an external leak. As others have said, a compression check and a leak down test will help in determining what’s going on inside your engine.

An engine with borderline ring-sealing can still perform quite well, so performance isn’t always a reliable determinator of low compression. Another source of oil consumption can be worn valve stem seals and/or worn valve guides, and it’s the nature of the beast that neither a compression check nor a leak down test will reveal poor valve stem seals/worn guides. And if you do a lot of highway driving, you may not ever notice any blue smoke from the exhaust.

[Author]

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