Hello,

I appreciate your time and advise

1998 Honda Accord EX with 160K miles

The #3 cylinder is 115 PSI, the other three are 170 to 175. The number 3 spark plug is black, the others are greyish. Im pouring two quarts of oil every 1500 miles or less.

I connect a compressor to the number 3 cylinder and I get a hissing sound coming out of the the number 3 spark plug camber and I can feel air coming out of the other three cambers. The number 3 cylinder is not holding the air pressure pumped into it while the other three are.

Question
1. Is this a valve adjustment needed? I did notice last night loud clanking from the valve cover. If I do a valve adjustment, do I need new gaskets? I replaced them at 90K miles.

2. Where is the oil going? It is not dripping on the ground.

Thank you very much.

 

your probably burning oil in number 3. when you jam air into number 3 cylinder, is it at top dead center on its compression stroke? probably a bad oil control ring.

 

I was told that if you put some oil into the cylinder then check compression, if it goes up then it's probably a piston ring not sealing (the oil helps seal it better temporarily), but if the compression is still low, it could be a valvetrain issue. Worth a shot, but I'm no expert and I'm sure someone else will come in with better advice.

 

That's the easiest way to determine if it is a cylinder/ring issue or a valve/valveseat issue.

If pressure increases with oil, its most likely a cylinder/ring issue.
If no difference its most likely a valve issue.

 

Burning/losing oil is interesting. Also the clanking noise in the top. I would recommend removing the valve cover and checking for any lose parts or broken components paying special attention to the problem cylinder. If no issue is apparent try replacing your oil. Check for fine or chunky metal. This may indicate rings and cylinder issues. Head gasket will usually burn coolant and or leave oil in the coolant.

 

Either way you have major mechanical issues. Sorry to inform you. Loss of compression is never a simple issue. When you checked the comp and used the gauge. Did you crank it at least 3-5x with the throttle wide open? You may have an issue with the entire piston at this point. Oil is burning as quick as it can burn and you have **** poor compression. So you have rings on both top and the bottom that aren't working. Any other symptoms you have? What were you doing with the vehicle when the issue started? Has the oil burning been getting worse and worse or did it just start one day real bad?

 

Yes, the number 3 cylinder is in it's TDC on compression stroke. I hear the air coming out of the valve cover cylinder hole

 

Great explanation Mad Mike, thank you.

So based on my symptoms, it appears I have a valve issue since I'm hearing and feeling air come out of the top valve cover.

Do I need to pour oil into the cylinder still to determine if valve or ring issue? Another questions is how much oil to pour into cylinder?

My big concern is if I fix the valve issue, then I later find out I have a ring issue as well as Accordturb 96 mentioned. How do I figure out if I have a valve and ring issue?

Thank you MAD_MIKE

 

Yes, I cranked the engine 3-5X with throttle wide open. Other than oil consumption getting worse, the car runs fine. When oil gets on the low side is when I hear the valves chattering.

I drove car just now and it runs great. No other symptoms.

Thank you.

 

If your compression does not change with oil added to the cylinder then most likely yes. Otherwise if the rings are bad they will not hold compression and the air rather than being compressed will escape past the rings and into the crank case where it will pressurize the crankcase. And can only escape through the PCV system or open port(oil fill in valvecover).
Yes, you should still put a few ounces of oil into the cylinder to make sure it is not a ring issue. If it is a ring issue the block will need to come out, to reduce down time I would opt for an imported(Japanese) engine.
If there is no change with the added oil most likely it is the valve, or possibly a head gasket, issue. The head will have to be removed and then the deck of the block can be checked. The cylinder walls can be checked for scoring. If it is damaged then I would hold off on fixing the existing head/block as the work needed would also be needed to simply replace the engine with a JDM engine.

 

Hopefully your issue can be resolved with a bit more research. If you have any more questions feel free to ask. One of us are bound to be able to help you my friend

 

Mad Mike, if it was a head gasket issue wouldn't he see oil in the coolant? Or the engine would be burning coolant up? Just tryin to pick your brain.

 

You are right^ it will leak, burn, or allow the combustion to enter the coolant chamber

 

^^ I'm guessing you meant allow the coolant to enter the combustion chamber?

 

head gasket issues could result in a few different possibilities ... considering the oil loss and the low compression I would say the head gasket is bad, resulting in a leak of oil into the combustion chamber which explains the black spark plug

if it's not leaking in between where oil and coolant are sealed off it won't necessarily leak oil into coolant and visa versa

has your car ever overheated ?