my 2001 lincoln ls overheat while i'm sitting in traffic

1) check your over flow reservoir. Is it properly filled? if it is not a) wait until the engine is cold. b) Remove the radiator cap and fill the radiator with water and tightly replace the cap (you can do the mixing of antifreeze later, you still have a few months before freezing temps come). c) fill the reservoir to proper level. d) turn the engine on and let it heat up about 20 minutes. There will be much air in the system that will bubble into the overflow reservoir. e) let the engine completely cool, it will then suck the fluid back into it from the tank. f) check the OVERFLOW reservoir tank ONLY! Do not open the radiator cap. Add fluid only to the "fill cold" line. After about 6 hours your vehicle should be back to cold. g) NOW here is the important part... Check the next day if the overflow tank is sucked dry. If it is then you have a leak somewhere. If there is no leak then.... MANY people think Antifreeze is a "coolant" that does the heat removal. It does not. WATER is what cools the engine, Antifreeze keeps the water from freezing in the winter and cracking the block. In summer months you can run a thinner mix where as there is more water than antifreeze, but in the winter it should be close as possible to 50/50 mix... AND don't ever buy premix 50/50, because you are getting ripped off... here is the math: a 1gal premix costs ~$12. So that is to say you are paying $6 for 1/2 gallon of water, when you can go to a store for a water refill for $0.35! Too much antifreeze in the summer does NOT help a vehicle it hurts it and could cause overheating.