Blue smoke but none of my plugs are fouled? howwww

[Ian]

the header pretty much says it all…i have a 1994 plymouth acclaim v6 3.0L engine. the exhaust pumps out blue smoke on warmup, after long lights, and after trips to the drive thru. i also go through a quart of oil every 300 miles or so, though that might also be due to me leaky valve cover gasket(which im fixing tomorrow). anyway certain that it was a bad ring or valve seal on one cylinder i removed each sparkplug one at a time and inspected them,suprisingly i came to find nothing but a slight white-yellow buildup on all 6…which i think is pretty normal after years of use for a plug. no blackness, no oil, perfect otherwise. also…i’m certain it’s not a head gasket antifreeze problem. their is no and has never been any milky oil, oily antifreeze, ect. also the smoke doesnt smell sweet…it smells very chemically and makes me wanna puke if i’m down wind of it.

…so yeah, im stumped. their has to be something i’m missing right? if its oil their obviously needs to be a problem in some system that is not directly related with the combustion chamber i would assume? otherwise all that i can think of if air to fuel ratios. anyway yeah, any input at all would be super awesome, thanks guys

Topic

[college man]

seeing its on start up,I’m gonna suggest valve guide seals. which lets small amounts of
oil on the piston tops and burns off at start up. Aslo check the PCV valve and hoses.
more in this link.

http://www.ericthecarguy.com/faq/finding-and-fixing-leaks?start=1#FindingEngineOilLeaks

[Andrew Harris]

I agree with the valve stem seals. Looking at spark plugs to determine engine condition is not an exact science and can be misleading, I wouldn’t put to much stock in that.

[Ian]

good to know. I was always under the impression that plugs were really good determinants for certain engine problems, guess not. Also i’ve checked the PCV valve 2 or 3 times over the last year. I unscrewed it and gave it a jiggle, and could clearly hear the bearing or whatever freed inside it, so i think its good. i suppose that its rings or valve seals regardless then. would you guys recommend I do a compression test and leakdown test before diving into the valve job or is it pretty obvious? thanks

[Andrew Harris]

How much oil does it use. its a 1994, car probably isn’t worth diving into the engine. If it only uses a quart between oil changes just keep checking the oil and make sure its full and then drive it till the wheels fall off.
Also the PCV valve should seal in one direction and allow flow in the other. so you can blow through both ends one should let you the other shouldn’t.

[Andrew Harris]

Also the spark plug pictures they show you in those c picture charts are usually extreme conditions. Most modern cars dont have near the problems that cars 40 years ago did, which by the way is probably about the time those charts were made.

[Author]

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