2002 Nissan Altman looseing anti freeze but nothing under the car

SOURCE: The anit-freez is leaking from the front passengre side.

that sounds definately like a water pump,without a doubt.
---Rinse all the coolant off the engine and radiator. After letting everything dry thoroughly, start the engine with the hood up, and watch for leaks. With this much coolant leaking you should easily find the leak. 

Could be a heater hose, or lower rad. hose. If not I would dye test it. Autozone has a loaner kit. Contains fluro dye and a blacklight. Makes it very easy to track it to the source. 
---------------------- a person having a same problem like your solved the problem .and what it was is as follows ------ I have a 96 DeVille and it had the same problem. What turned out to be wrong was that my car has 2 fans, 1 should come on when start the car and the second comes on when the engine is under a heavy load (ex. stop & go traffic, a/c running on a very hot day). My primary fan wasn't working properly and I had to take to the shop to correct the problem. 
------------- Unfortunately the two previous answers will not cause the coolant to spew out when you shut the engine off. The only thing that will cause that is excess pressure in the cooling system. Just about the only thing that will cause that is a head gasket. Most Cadillacs from the early 80s on have aluminum heads. It is very commom for an aluminum head to become warped when the engine overheats. When this happens a crack can form between the head gasket and the top of the cylinder block allowing pressure to get into the coolant. This in turn may cause a coolant hose to expand and allow coolant to spew out, it can also cause the radiator cap to release coolant, a good radiator cap is designed to release pressure when the pressure goes above the designated psi. The fact that it is not boiling over while running indicates that most if not all the rest of the cooling system is allowing the water to flow. The most common cause of overheating in engines is that the thermostat gets old and sticks. It only has to stick one time to cause the engine to over heat enough to either damage the head gasket or even cause a crack in the cylinder head. Take the vehicle to a garage and have them do a pressure check on the cooling system. After they have applied pressure to the system they will allow the engine to cool for a short while. If the pressure drops very much they should then remove each spark plug in turn and check the cylinders to see if coolant is in in them. If so that is the evidence that the head gasket is bad. If there is coolant in the crank case oil pan also, that indicates that either the head gasket is completely gone or that the cylinder head is craked. Depending on your goegraphical location it could cost around $1000.00 or more per head to have the heads milled and the head gasket replaced. If the car is over 8 years old or has more than 100k miles on it you will be better off to have the water pump, timing chain, camshaft and crankshaft timing gears replaced at the same time. Depending on the cost of such you may wish to check with someplace such as Dr. Motorworx to have the entire engine replaced. It can sometimes cost less to do that. And these shops usually not only garrunty their work, but usually give anywhere from 1 to 3 years or 36k warrunty on the engine. I hope this has been some help to you. GOD Bless! GLORIFY GOD!------------also this is someones personal experience.

SOURCE: How do I put in freeze out plug?

The easy solution is to get a rubber expasion plug to replace the original brass plug.

Dave C

• 1050 Answers
• Posted on May 14, 2009

SOURCE: anti freeze leeking

I have seen a couple of these now with headgasket leaks to the outside of the block just as you describe. I solved them both with a stop-leak additive, not something I would normally use, but I really didn't want to pull the heads because the exhaust studs always break on these engines. I would find out for sure where the leak is before proceeding though. If it's a hose or frost plug, you'll have to repair it properly.

SOURCE: Fan will blow. Temp gauge comes up to normal.

sounds like the heater core is leaking.

Phil Lovisek

• 726 Answers
• Posted on Dec 08, 2010

SOURCE: My 1997 Nissan Maxima 4 door sedan is leaking

could be the water pump. where is the coolant coming from?? behind the a/c compresor?? if so, you need a new water pump. need to know location of the leak or at least general location if you can not get exact.