What is typical the problem when your car runs hot while you're sitting at a red light but cools back down when you drive off??
Sounds like the water pump impeller is shot. The water pump circulates coolant around the engine, you probably notice the engine presently overheats in traffic or under load but may cool when driving under light engine load on the freeway. On the freeway air rushing through the radiator will cool the engine. I'd say it's time for a replacement.
If your car has over 80000 miles on it a common problem is the fan clutch even though if spinning it may be spinning to slow . A good test is to shut engine off after engine is warmed up and if fan still moves easily by hand the clutch is problably the problem
How can I find out what is draining my battery rather quickly? 2002 Ford Eddie Bauer, Ford Expedition
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