2000 LS cooling system is a very tough system to diagnosis. Any kind of air in system will totally stop the flow and cause it to heat.That is the reason it has 2 places to bleed the air from the system.The one at the engine where the upper hose connects and one beside the brake booster near the degas bottle(rubber tube with a screw end).
The cooling fan is also hydraulic and has it's own power steering pump.
The good thing about this system is that it uses a cylinder head temp sensor that measures the metal temp and not engine coolant temp. When the PCM sees the CHT reach a certain temp it will start shutting down 4 cylinders at a time and use these cylinders as actual air pumps to help cool the engine down.If this does not work it will then shut the engine down totally until the temps come back down.
The most common problems we see are thermostats,crack degas bottle,or a leak somewhere,and of course air in the system. Have not seen a cracked head yet however did see one that pushed the plug out of the cooling port in the head but this also filled the oil with coolant.
Have also seen cooling fans that would not work until PCM demmanded high speed,caused by a weak power steering pump.
Feb 22, 2009 |
2000 Lincoln LS