Is my truck actually overheating?

I have 2001 Tacoma trd. I got home from work and about 2.5 hours later I went to leave the house and my temperature gauge was reading over the red mark. I didn’t drive it and the next day a tried burping the coolant system and no air came out and the thermostat seemed to be working fine. I then drove it around for about 25 mins without a problem and parked it for about 45 mins. Went to leave for work and the gauge was reading over the red mark again. I shut the engine off and turned the key so just the electronics were on and it read normal temp. Started it and it read normal still. I still didn’t drive it and I’m wondering what the issue is?

 

Welcome to TW

 

Thank ya, just bought the truck about a month ago too.

 

So when you were driving it around the temp was normal, then it sits for a while and THEN the temp reads high?

That's odd.

Do you have an OBDII code reader? They are generally pretty cheap, and you can get ones that are bluetooth and connect to your phone that runs an app like Torque Pro. There's a plug down by your right knee that it plugs into.

Once it's hooked up, you can read the direct temp from the ECU, rather than the temp from the gauge cluster, which isn't really a temp gauge anyway.

 

@Black DOG Lila
@eon_blue

 

Is it actually overheating when the gauge hits the red (hope not because by the time it hits the red mark you've done serious damage). You would know it because the coolant would be boiling in the reservoir

If it's not actually overheating then you've probably got a faulty temperature gauge sensor

 

Sounds electrical. The temp sensor works by changing resistance - the higher the temperature, the lower the resistance. If the sensor is shorting out, that would be a resistance of 0 and would give you a fully overheated looking gauge.

I'd look at the wiring around the sensor and see how it looks. If its fine, I'd just replace the sensor.

What engine do you have?

 

I have the 3.4 liter v6 and yeah there’s no coolant boiling in the reservoir ever. Thank y’all!

 

can you feel coolant moving in the lines when the motor is on?