If you think you might be burning oil you would do a compression test in order to check for blowby (i.e. bad rings) If one or more of your valves weren't working you would have much more serious problems then low compression and you would def know it. If you are running rich your plugs will be dark not wet.

 

If it's misfiring in one of the cylinders, I would defintely do a compression check. Just buy a quart of oil and go to your mechanic to have it looked at. Also check your spark plugs to see if they are okay.

 

P.S.
Compression checks can also denote head gasket failure, And a leak-down test would prolly be the best thing for him, thanks for mentioning that FatalJRA.

 

Check your o2 sensor also; does it put out blue smoke at all times?...or only til it warms up?

 

Well, the o2 sensor can indicate if it's burning too rich. If there is any oil build-up on the sensor, after the engine is at normal operating temperature, the build-up will most likely burn off. However, the carbon-based soot from unburned fuel will stay on the o2 sensor for quite some time, even at normal temps. So it's a decent indication of burning rich, but not burning oil. Although it is the easiest way to tell if you are burning oil as opposed to looking at unburned fuel.

 

vertstanggt, calm down man...dont get your panties in a twist everytime u think somebody isnt right...burning oil can be alotta things...now they said a vlave wasnt working correctly which explains a good amount; it also causes other thing sin the cylinder to lag; injectors; lagging injectors causes fuel to leak, which causes it to be unburned, thus giving you a rich exhaust flow, which can be black, blue, w/e you want...also, this lag, and leaking of unused gas causes the plugs to become wet with gas; this can even occure when u have bad seals...every plug gets black as soon as u use it, its just a composite from the spark...WHY cant we all just get along???...lol

 

This is all I found about vavles other than someone reccomending they rebuild the head if they were going to do rings. They were talking about the pcv not pvc (positive crankcase ventalation) not the valves you are thinking of. If they were having intake or exhuast vavle problems they would know from more than smoking exhuast. Like they would be running on three cylinders or something much worse. The only way that would be involved is if the seals weren't doing their job they could get oil in the runners or right into the cylinder depending on which one it was. Also different colors and buildup on the plugs can tell you a lot about how your engine is running, too rich, lean, burning antifreeze, ect. They are not always black and dry or black and wet. And please stop with the dumb personal crap, if I disagree with your opinion it's becuase I think you left something our or you are wrong. I'm not trying to tarnish your all important ego

 

does anyone know how to clean o2 sensores? Or should i just get a new one?

 

If it is bad/ worn rings causing the ignited gas to blo-by the piston and pressurize down into the crankcase then you sould see white smoke billowing out of your oil cap hole when you remove the oil filler cap and also you should see white cakey moisture residue collecting on the inside of the oil cap.

This always indicates bad rings.

Is your oil cap clean ?

Dt

 

99clipse, to clean the o2 sensor, soak it in some carb cleaner(any brand, doesn't really matter, just go for the cheap stuff if you like), and after a few hours, the build-up will be able to be cleaned off using a small screw-driver. Getting a new sensor isn't such a bad idea though, your sensor is going to be 6 years old soon and...well...it won't last forever. But if it still works, i'd say jusst clean it up and use it.