This week i pulled the plenum. I had to order some extra parts so the car is just sitting there. Yesterday i noticed there is a huge puddle of oil underneath the car. This has never happened before(even if the car was left sitting there for days with the plenum on), what could of caused this?

any gasket or seal in your motor could have caused this..............

start looking to see where it came fromget under it and look....my na had a real bad leak on teh rear seal of the oil pan...but it also had leaks on all valve covers and rear main and front main... seals go bad... only way to find is to look

I was told that i should reseal the lower valve covers because they leak. How would i go about to resealing the valve covers?
Modified by emiliog2276 at 7:42 PM 1/10/2010

cam covers are what i called valve covers.... they sell gaskets at autoparts stores....

How difficult is it to replace? My plenum is already off.

Easy, if the plenum is already off. Take the spark plug galleys off, unbolt the lower cam covers. Tap them with a rubber hammer and block of wood until they come free. There is no gasket for the lower covers, they are only held on with sealant. I used Permatex Ultra High Heat Copper and they never leaked again. Just make sure to clean the old sealant off the cover and head. If you are leaving a puddle though, then it might be something else. Get the car on a hoist and inspect, but either way the covers should be resealed as they always leak of they've never been done before. Also check that the upper cover bolts are snug. They use a rubber gasket but it doesn't often go bad.

So the removal of the Exhaust Cam Valve Cover are easier then? Should i replace the Exhaust Cam Valve Cover Plugs underneath this cover? The nissan rubber ones are 3 bucks and CZP sells the aluminum pair for 20, should i pay the extra money for that?

possible leak from rear engine seal or oil filter tree/assembly. Possible suspects on any if not most cars.