420a temp acting up.

[jboyd04]

okay so i have a 98 eclipse 420a m/t. When im at idle the temp gauge will read half creep to 3/4 sometimes a hair higher and slowly settle again repeating this over and over. Now as im driving at idle same results but when i get on the gas it will cool off. mind you head gasket has 1205 miles on it. so that i ruled out. I changed the thermostat twice with out any different outcome. I had also tried burping the system a few times. So im at a loss of ideas so if anyone has had this issue please reply with a suggestion. Any help at all would be greatly useful.

 

[grothe3297venge]

Do you hear the fan kicking on?

 

[islandertalon]

Do you have a way to verify the temperature the ECU is seeing? The ECU and gauge use two different sensors, so it could be the sensor or wire to the sensor acting up.

When you said "driving at idle" do you mean driving at speed but in neutral? If so did you change the water pump when the head gasket was done? Sounds like the pump may need the extra rpm to get enough coolant flowing to the rad, or overcome a big air bubble.

 

[Terrancep7]

Change your coolant sensor and buy a 180 degree thermostat also make sure you have enough coolant in the system and she'll run like a dream

 

[jayson427]

Bet it's a bad wire going to the cts which mine does the same thing. If you follow the wires that run over the valve cover by the timing gear you will probably find a short. Try to run a voltage meter and see if it's dropping while the car is running.

 

[jboyd04]

The fan is kicking as far as a way too see if the gauge and the ecu see the same temp i do not have a way to do that. But i will definitely look into the sensor. As well as check for the short i appreciate these reply's folks.

Thank you all for the quick replies unfortunately the car is totaled due to someone running a stop sign and nailing the car. So it has been an absolute pleasure being apart of this forums.

 

[DEADKITTY]

Sorry to hear about your car. Hopefully everyone is okay.