I just got my truck back from an accident last week and noticed that it is overheating. I had noticed that was running hot over the winter on the warmer days, but now it's bright as day. The car starts and runs fine everytime but I'd say within 5 min of driving the water temp needle is at the top end and while driving and sometimes even at idle it will go into the red and the check gauge light comes on. It will go up while driving and letting off the gas it will drop back down and the light goes off but it doesn't go down very far though. Any thoughts?

 

is the fan working? check the anti-freeze level.

 

The important question, is it actually overheating?

If it truely is going all the way up to red, it should be boiling over, the overflow tank should be getting filled with boiling coolant and then spilling out onto the ground when the tank is overfilled.

If not, then more than likely a malfunctioning coolant temperature sending unit. There are two coolant temp sensors, both located in the thermostat housing area. One is the coolant temperature sending unit, it just reports to the gauge. The second one is the engine coolant temperature sensor, it reports to the ECU. It is a bit of a checks and balances system, if it was really overheating, the ECT sensor would report the same to the ECU, it would go into overtemp protection mode, altering spark timing and locking out certain transmission gears (If automatic) to prevent further damage from occurring. Plus the Check Engine light would be flashing.

 

Could be your thermostat is toast and in the closed position. With the thermostat closed, there is NO coolant circulation.

Also, welcome to RF, make a signature with your truck details (year, engine size, drive train, etc.) It'll make it easier for us to help you out.

 

His profile says it's an 02 and he's posted in the 3.0 forum so that narrows it down a bit.
It sounds like the water pump failed , but in only 8 years ?

 

thanks for the suggestions I will look for all of them on the ride home today. It is an auto. I haven't noticed it alternating spark or anytjing with the trans, but I haven't been riding it hard when it has the light on I try to coast for a bit until it goes back down. As far as the overflow I haven't noticed any excess leakage, but I will keep an eye on that to be sure. I will also let it run and make sure the fan is coming on also , but the last I checked it does, I have pretty short drives here nothing over 10 miles really and mostly highway mileage. Thanks again I will update later today with what I saw

 

Its the water pump.