Replacing the PCV Valve 1999 seville sls
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It's an extremely simple and inexpensive maintenance item. It costs about $2 and takes about 5 minutes to put it in with zero tools required. Probably a good investment.
A PCV valve is basically just a hollow tube with a weight in it that is attached to a spring. The weight and spring modulate the air flow through the valve, thereby ensuring that oil vapors and blowby gases in the crankcase are burned instead of being exhausted to the atmosphere where they can contribute to smog and other air quality issues. Air flow through the valve comes from the intake manifold vacuum, and supply air comes from some point after the air filter so that dirty air doesn't contaminate the oil. Without the PCV valve, there would be high vacuum in the crankcase and it could be hard to remove the oil dipstick while the engine was running. Because oil and blowby gases pass through the valve, it can get crudded up with that gunk and stick open or shut. The spring can become detached from the weight so the proper air flow is not moving through the valve. All sorts of weird symptoms can be tied to a PCV valve problem.
A PCV valve is basically just a hollow tube with a weight in it that is attached to a spring. The weight and spring modulate the air flow through the valve, thereby ensuring that oil vapors and blowby gases in the crankcase are burned instead of being exhausted to the atmosphere where they can contribute to smog and other air quality issues. Air flow through the valve comes from the intake manifold vacuum, and supply air comes from some point after the air filter so that dirty air doesn't contaminate the oil. Without the PCV valve, there would be high vacuum in the crankcase and it could be hard to remove the oil dipstick while the engine was running. Because oil and blowby gases pass through the valve, it can get crudded up with that gunk and stick open or shut. The spring can become detached from the weight so the proper air flow is not moving through the valve. All sorts of weird symptoms can be tied to a PCV valve problem.
I think 99% of PCV valves are changed needlessly. Granted, I don't work on cars for a living, but I have yet to see a bad one. Shake it, if it rattles, it's good. If you really want to clean it, hold your finger on one end, spray some Gumout in it, place your thumb on the other end and shake. Then pour out the Gumout and replace it.
After my last oil change, I checked and the level was about 3/4 inch above the max fill line. When I complained to dealer about it, they said not to worry the excess oil would be blown out the PCV and get burned. Wife drove car 2 hours long trip before getting oil corrected, and I checked the level when she got back, it was at the max line. Is it really possible oil went out the PCV?
I found oil puddled on rear of engine down in the valley below heads.
1994 Seville STS
Can you be more specific about the PCV location, mine is more than likely a mess?
A photo would be great.
Coincidentally the engine started overheating afterwards.
I found oil puddled on rear of engine down in the valley below heads.
1994 Seville STS
Can you be more specific about the PCV location, mine is more than likely a mess?
A photo would be great.
Coincidentally the engine started overheating afterwards.
Rfishing, it's normal to have some oil down in the valley. I mean it's never been cleaned down ther in what? almost 12 years? I have some oil down in the valley of my 94 but I'm not worried. When it's daylight I'll take a picture of the PCV valve and inspect mine just because I haven't... ever...
Look on the rear cam cover (passenger side) can't miss it. The PCV takes crankcase gasses and routes them through the intake so it will always be oily when you pull it and look at it. If the crankcase is overfilled, the crankshaft counter weights will whip the oil into a mist and then be sucked through the PCV, into the intake and burned (normal). That is why it is said that topping off the crankcase to the max mark will only exasserbate the oil consumption issue.rfishing said:
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