07 nissan sentra valve stem leaking

SOURCE: Dashboard and tail lights out on 97" Nissan Sentra

i would check the connectors under the dash they have a tendancy to get loose are get hot and short a fuse this is most likely the problem...please rate this....

SOURCE: Water under driver side floor

It may be due to the air conditioning hose being blocked. Therefore the water must be backing up into the vehicle, under the carpets and into the back seats instead of flowing out

SOURCE: 93 Nissan Pickup 2400/12 valve

I would venture to guess that a timing chain guide broke and the chain chewed a hole thought the timing cover. The timing cover also has coolant passing through it where the water pump is attached. If you were running a multi viscosity oil, even it it were a 20-40 and got surprised by a zero degree day, I doubt seriously, it would cause that to occur. That series engine had problem s with timing chain guide failures. However, there usually is some chain rattle well before a disastrous failure. Most of my customers noticed the chain noise before it has caused catastrophic damage.
Sorry you have suffered such a loss. Good luck on your repair. A used timing cover would be the cheapest route. A place in Dallas called Bishops, buys engine cores, dismantles them, evaluates them, cleans the good parts up and sells them at very reasonable prices. They ship all over the country.

SOURCE: tire size

Front Tire Size P185/65R14 Rear Tire Size P185/65R14

I hope this will solve your issue.

Good Luck.

If my solution proves useful please accept it.

Regards
Arjun

Harvey N Tawatao

• 3854 Answers
• Posted on May 29, 2009

SOURCE: Replace Valve cover on 2002 Nissan Sentra

Are you sure the Valve Cover and not just the Valve cover gasket??
Any ways go to Auto Zone and pick up the Valve cover gasket, RTV Silicone selant, Gasket Scraper, and a can of Brake parts cleaner spray.
Disconnect the battery cable from the negative battery terminal, Remove the items which are in your way: Pull the spark plug wires off the spark plugs and remove them from their brackets, remove the PCV hoses, and remove the throttle cable from its brackets and position it out of the way.

Loosen the fasteners in this order, I believe there are 11 bolts holding the Valve cover down. Remove one bolt and count to the next 5th bolt and remove it and count to the next 5th bolt and remove it, do this till all the bolts have been removed on a circular pattern. Carefully remove the valve cover from the engine head.

If your just going to replace the Valve cover gasket,  Remove the gasket from the valve cover. Thoroughly clean the mating surfaces of the valve cover and the engine head. Use a gasket scraper to remove all traces of old gasket, and then use the Brake parts cleaner to clean any remaining oil from the surfaces.
If you bought a new Valve cover, Apply RTV silicone sealant to the gasket and engine head around the cutout areas of the valve cover. Note you still have to clean the heads on the engine. Lay the new gasket in the groove in the valve cover.  Reinstall the valve cover with its new gasket on the engine head. Tighten the bolts in the same order you removed it in. Do Not Over Tighten the Bolts that hold the Valve Cover down, you'll crush the new gasket and will get an oil leak.
Note: If the valve cover does not come off the engine head easily, use a block of wood and a hammer to bump it in an attempt to jar it loose. If absolutely necessary, you may slip a flexible putty knife between the head and the cover to break the seal.
If you purchased a valve cover gasket kit, don't forget to replace the small rectangular gasket and the spark plug seals as well while you have the valve cover off the car. You may buy some Brake cleaner to clean off all the oil which has leaked all over the engine. 
DO NOT attempt to pry the cover off the head using a screwdriver or chisel. Be very careful not to introduce foreign matter into the engine. If you get anything (dirt, metal shavings, bits of old gasket) into the engine. 
DO NOT over-tighten the valve cover fasteners. On the engine, the fasteners need only 17 to 34 in-lbs of torque.

Your A/C system has a leak in it. all system has a slow leak and common, You can get a re-charge kit at Auto Zone to save some money, but if your A/C needs charging again in 2 weeks or less then there is a larger leak due to a bad seal and is cheaper to have a A/C shop locate the leak and replace the seal that has gone bad.
Good luck and hope this help. keep me posted, be glad to help.