Coolant temperature gauge issue

[Circa Surviven]

I've noticed over the past two days that my coolant temperature gauge goes to the 3/4 mark. I googled this and looked through the threads. I have already replaced my water pump and thermostat. I also noticed that when I start the car the gauge is already at the 1/4th mark and quickly got up to the half way point before my oil even started warming up. The engine was cold to the touch but the upper radiator hose seemed very hot. My OBD2 reader reads the coolant at the appropriate 82-86 degrees Celsius. I checked the fan clutch and it seems to be okay. Do I replace the coolant temperature sensor/switch in the lower radiator hose and radiator or what? I don't have any bubbles at the bleed screw and no loss of coolant.

[yhp2009]

Seems like your coolant temp gauge is at 1/4 to begin with even with engine off. Perhaps the gauge itself has deviated from "zero" and need to be physically nudged back/zerorized? Unless you computer also tells you the same wrong temp

[sapote]

The engine was cold to the touch but the upper radiator hose seemed very hot.

Which part of the engine was cold? Sure the head was hotter than the upper hose. How hot was the lower hose -- held in hand for 1 minute?

[jbfrancis3]

Seems like your coolant temp gauge is at 1/4 to begin with even with engine off. Perhaps the gauge itself has deviated from "zero" and need to be physically nudged back/zerorized? Unless you computer also tells you the same wrong temp

Totally agree. With ignition off (like you have in 2nd pic) the needle should be full-left (like the fuel gauge). Seems the issue is confined to the instrument cluster.

[jet_dogg]

I would change the sensor before I did anything else.

[Circa Surviven]

Totally agree. With ignition off (like you have in 2nd pic) the needle should be full-left (like the fuel gauge). Seems the issue is confined to the instrument cluster.

Is it normal for the upper radiator hose to get extremely hot in less than 10 minutes after starting? I'm just concerned it may actually be overheating and I'm going to toast the motor. After running for a bit the engine cover, expansion tank and upper hoses are too hot to touch.

[Circa Surviven]

I would change the sensor before I did anything else.

The sensor in the lower radiator hose or under the manifold?

[jet_dogg]

Start with lower rad hose first and if that doesn't work do the second.

[Obioban]

Pretty sure this is a gauge issue, with it being at 1/4 with the engine off. It should always be a the beginning (?) of the gauge with the engine off.

[Kevin2772]

I dont think he is saying its at the 1/4 mark turned off, hes saying when he starts the car, the gauge jumps up to the 1/4 mark. My car does the same sometimes, but i just figured thats because its warm enough in my garage. Maybe im wrong as im chasing a cooling gremlin as well of 3/4 heat in 96 degree high humidity weather with the A/c on. Only happened once and i havent been able to replicate it again.

[Circa Surviven]

I dont think he is saying its at the 1/4 mark turned off, hes saying when he starts the car, the gauge jumps up to the 1/4 mark. My car does the same sometimes, but i just figured thats because its warm enough in my garage. Maybe im wrong as im chasing a cooling gremlin as well of 3/4 heat in 96 degree high humidity weather with the A/c on. Only happened once and i havent been able to replicate it again.

I'm going to verify it does it again today with the car cold overnight. It was actually staying at 1/4 with the car turned off.

I think it was close to 1/4 starting it overnight yesterday though. After trying to bleed the air yesterday just to try the simplest cause, the gauge started hitting the red. (Car was not jacked up in the front during bleeding). OBD2 temperature never went over 87c though.

[ZiMMie]

your cluster is broken.

[yhp2009]

Is there a way to get the coolant temp reading straight from the computer so you can compare it to the gauge? Then you'd know for sure which needs fixing

[Obioban]

[jbfrancis3]

Is it normal for the upper radiator hose to get extremely hot in less than 10 minutes after starting? I'm just concerned it may actually be overheating and I'm going to toast the motor. After running for a bit the engine cover, expansion tank and upper hoses are too hot to touch.

Extremely hot is relative. This vehicle gets up to operating temp in less than 10 mins. Yes normal coolant temps are too hot to comfortably touch.