SPONSORED LINKS

Started to overheat while idling parked

Tiny
VICMARMIL
  • MEMBER
  • 2002 CHEVROLET MONTE CARLO
  • 3.8L
  • V6
  • 2WD
  • AUTOMATIC
  • 112,000 MILES
The temperature gauge bottoms out then goes back up then down while driving. If I am stopped at a red light, when light turns green it occasionally shuts off. I was idling while waiting on a friend and it began to overheat. No lights came on, no engine or coolant light. I could feel that liquid popping and shut it off before it steamed.
SPONSORED LINKS
Thursday, November 21st, 2019 AT 2:05 PM

18 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good afternoon,

Did you check and see if the cooling fan was working?

https://www.2carpros.com/articles/replace-electric-fan-motor

How old is the thermostat?

https://www.2carpros.com/articles/replace-thermostat

Did you verify the coolant level?

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Roy
Images (Click to make bigger)
Thumb
Thumb
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
+1
Thursday, November 21st, 2019 AT 3:12 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
I ran the heater and the temperature came down. The temperature gauge has been fluctuating for the past week between normal operating temperature and 0. I did not notice any odor at the time it was too hot or after driving with the heater on.
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 3:19 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Okay, got it.

All my questions still stand.

Roy
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 3:22 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
I do not know the age of the thermostat because I bought the car less than 6 months ago. I do believe the fans are fine and no fluid leaks. I did add some water just to get home. Should I drain the system and replace fresh coolant as well as get it diagnosed?
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 3:27 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
I would replace the thermostat, add new coolant and drive the car and see if it is fixed or if it still has issues.

Roy
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 3:29 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
Because no warning light came on, I am thinking that some fuses might also need to be replaced?
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 3:31 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
Should the coolant be drained completely?
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 3:33 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
No, since you said the fans are working, it is not electrical.

Yes, remove the lower hose to get it all out.

Roy
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 3:45 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
Was that no to the fuses? Shouldn't my temperature warning light have come on?
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 4:23 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
No to the fuses. When it gets very hot, there will be a warning but that is not the reason for overheating. It is just a warning.

Roy
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 4:27 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
I understand that the fuses have nothing to do with overheating.
Totally separate issue. My concern being that the dash lights are supposed to warn me of engine trouble and/or temperature problem and they did not.
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 4:46 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Okay, that could be the coolant sensor that sends a signal to the ECM to turn on the warning light as well as making the gauge readings correct.

Roy
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 4:52 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
Is the coolant sensor related to why the temperature gauge on my dash kept dropping then going back to normal?
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 4:57 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Yes, it is. It most likely is reading correctly since the cooling fans were coming on as the temperature got too high.

Roy
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 4:58 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
Okay, so I likely am looking at replacing thermostat and coolant sensor and drain and flush the cooling system?
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 5:01 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
As a start, yes. Replace them and see what happens.

Roy
Was this
answer
helpful?
Yes
No
+1
Thursday, November 21st, 2019 AT 5:04 PM
Tiny
VICMARMIL
  • MEMBER
  • 10 POSTS
Thank you Roy. You have been very helpful.
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 5:06 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
You are welcome.

Always glad to help.

Roy
Was this
answer
helpful?
Yes
No
+1
Thursday, November 21st, 2019 AT 5:08 PM

Please login or register to post a reply.

Related Engine Overheat Content

Is Your Engine Cool Enough to Check?
VIDEO
Is Your Engine Cool Enough to Check?
Instructional repair video
Overheating Symptoms
GUIDE
Overheating Symptoms
An overheating engine is never a good thing to have happen. If the problem is caught quickly you can save the headache of a major engine repair. Knowing the information from...
VIEW MORE

Sponsored links