91 LS overheats bad at stoplights

[Mike61096]

So I noticed when I was in stop and go traffic yesterday, my car would overheat really bad when I sat at a stoplight for too long. As soon as I started driving again the temperature would drop down to below half again. The temp gauge was red lining so bad I actually thought the engine would shut off. I'm thinking it's possibly a faulty thermostat, but I don't know how to go about diagnosing the problem. Any help is greatly appreciated.


Sent from my iPad using Tapatalk HD

 

[thenoxus1]

Sounds like the fans aren't kicking in. Let it sit turned on and listen to see if the fans start to go on. That could be a basic issue causing it.

 

[dopematic]

Check coolant level.

To check faulty thermostat.
- take out thermostat and drop it in a pot of boiling water to see if it opens up or not.

Are your fans kicking in?

 

[dlo253]

That^

 

[EyeKhan]

That happened to me in my '99 LS. Fans kicked in, too. I found out I had low coolant levels. Didn't know why until I found out, months later, that the heater core was dumping coolant inside my car.

 

[DC Guardian]

Refill coolant, possible slow leak

Sent from my DC4