Oil in Cylinder Chambers

[Mike]

So I’ve still got that lawn ornament of a 99 Honda Accord 4cyl (190k miles or so) in my yard. Last time I checked in I’d just done an ECU swap but had fried the Main Relay. Put the new main relay in and started the car, seemed fine! Let it idle awhile then drove it in a big circle. Did OK for maybe a minute or two, then stopped and has never started again.

The immediate cause seems easy to diagnose: oil on the spark plug electrodes.* Pull the spark plugs out, clean them off, put them back in, crank it for a bit (it may catch a little) then pull them back out and they are covered in oil again.

Since two compression tests have come back roses, I’d suspect the problem is up top. But here’s my question: why all 4 cylinders? If leaky valve gaskets were the problem, for instance, how likely is it that they’d go bad in all 4 cylinders? Is there something else that could cause an oil leak in all 4 cylinders that’s a more likely explanation?

*If you remember, my previous problem with no start had been thick carbon build-up on the spark plugs electrodes, which was blamed on poor timing. It seems very possible to me the problem has always been this oil leak, but it’s somehow gotten worse.

EDIT: Where I had previously written “terminals” has been corrected to “electrodes”.

Topic

[Joseph C]

^^ so.. This car cranks? And DOES have good compression?

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[Mike]

Correct. But I’ve just edited the above to correct terminology: the oil is on the spark plug electrodes, not the terminals as I previously wrote.

[Joseph C]

[quote=”Wretzel” post=161726]Correct. But I’ve just edited the above to correct terminology: the oil is on the spark plug electrodes, not the terminals as I previously wrote.[/quote]
Ok.

So you suspect that for some reason, oil is flooding the cylinders and thus fouling it out enough to not start, right?

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[Richard Kirshy]

[Richard Kirshy]

How likely are all 4 seals to go bad…
Consider the age and mileage also they have been exposed to the same condition(s)
So if one fails, chances are reasonable that all can.

[Mike]

Exactly. When I take them out after trying to crank it, the electrodes are covered in oil, enough so that I imagine a spark couldn’t get through it.

[Mike]

Thanks nightflyr; I suspect something like that is the problem. One thing though; I don’t have oil in the spark plug wells. (I have replaced the spark plug well seals, previously.)

[Richard Kirshy]

My bad….. :blush:
I would think the next logical place to look then would be valve seals….
Have you noticed excessive bluish smoke from the tail pipe?

[Mike]

No, it was never smoking under normal conditions. Back when this first started, the car started to choke and stall out, which became more frequent until the car finally wouldn’t start at all. There was a lot of carbon build up, on the spark plugs and downstream on the O2 sensors. Those have all been replaced. I ran a lot of throttle body cleaner/gumout through the intake before then, which caused a fair bit of smoke and some small carbon bits to spew from the tailpipe, but otherwise no smoke.

[Richard Kirshy]

Have you looked down to see if there is oil build up in the cylinders?
Only 2 ways for oil to get to the plugs ( warped or cracked head or block not withstanding)
Valve guide seals or by passing oil from the rings.
And considering you state your compression tests show good.
I would look at the seals.
Strange you have oil on the electrodes, but show no signs of burning oil out the exhaust

[Mike]

Getting that much oil into the combustion chamber so quickly points to several possible problems. Could be worn/stuck oil control rings, worn valve guide seals and/or worn valve guides. In more general terms, it sounds like an engine with worn internals, regardless of what the compression test and lack of tailpipe smoke seem to indicate.

You describe this car as a lawn ornament. If it has spent a very long time sitting, it’s also possible that the oil is so diluted with accumulated condensation that the thinned-out oil is getting past everything that is supposed to be keeping it out of the combustion chamber.

[Mike]

OK, here’s a major update: it’s not oil.

Damn sure looks like oil. But rubbing it between my fingers, I can tell it’s actually gas. There is SOME oil in the #4 cylinder, but, it’s still mostly gas I think.

Well, that explains the lack of smoke.

Got to think on where to go from here.

[Richard Kirshy]

Excessive fuel from the injectors….
Might try a pressure test to see if the injectors are leaking

[Mike]

Do you mean a leakdown test?

[Shaun Flichel]

Fuel pressure test

[Author]

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