[slick3783]

Hello,
I have a 2003 Optima that has approx 42,000 miles on it. Within the past three weeks I have noticed that the temperature gauge will go up near the red zone while driving. I can turn the A/C off and it will go back down to near normal. I have changed the thermostat, the radiator cap, and the radiator is full. There is no leaks I can find and both fans seem to turn all the time. I have also put a volt meter on the coolant temperature sensor and it seems to be within specs, along with the wiring harness. I have also swapped the fan LO relay with the fan HI relay.
The car may run at normal operating temperature for a week or so, and all of a sudden it will begin to run hot all of a sudden. I have no idea what's going on, and I don't have a Chiltons manual. Does anyone have any suggestions?

 

[Spec SX]

hmmmm......you have replaced and checked alot of what I was going to suggest. It might be the first signs of a water pump going. When was the last time the system was flushed?

 

[Spec SX]

I had the following emailed to me by leoleo


hi

i think u can check the heating valve, maybe ur problem bcz. of the heating valve.
hope u'll solve the problem soon

thx

leo

 

[ahfrederick]

yeah, same here.. hope it helps.

 

[seacam]

Hello Slick,

Years ago I had a Ford Capri doing and showing excactly the same symptoms.

I replaced the thermo' nothing doing, removed it altogether, still showing hot,
went from mechanical fan to electric', nothing and the problem was intermintent and infurating, it turned out to be the water pump.

I know you say you checked the coolant temperature sensor and it seems to be within specs but that is still a strong suspect.
Seacam

 

[Daytonabob]

I would certainly think that your ride is still under warranty. Let the dealership deal with the problem to fix it

 

[Daytonabob]

Since you have that mileage on the car,I would also check the condition of the transaxle fluid. If it needs changing, it will heat up and cause the overheating in the cooling system. Let us know about that too...