Q: Vehicle is starting to overheat at idle.

asked by on October 21, 2016

Hello there. My Silverado has a cooling issue when sitting idle. If left for too long it begins to overheat with the temperature climbing steadily towards 235 and in a matter of no time, if left unattended for too long, will reach 260 (I have only done this once. Shut the truck down every time I leave it now). When driving down the road, the temp starts right at it just a hair below 210. When sitting at idle for lengths of time, as long as the heat is on full blast, it will just go past 210 reading in between the second and third line. I'm trying to determine if this is a failing fan clutch, thermostat, water pump or some combination of the 3. I have a degree in auto but have never been faced with this sort of issue. I'm not one to just throw parts at a vehicle either. I want to do the job properly and not have any other issues or unnecessary expense. Thank you in advance for your time and response on the issue.

My car has 157000 miles.
My car has an automatic transmission.

There is a technical bulletin TSB 04-06-02-006A that covers the issue you are getting. It states that the cooling fan clutch will disengage at lower rpm’s of the engine and will allow the engine to overheat. You should replace the cooling fan clutch with the new design that engages at the lower engine speeds and temperatures.

You may have to supply vehicle VIN to get the correct one for your motor. There are a couple different dealer parts listed depending on the motor ID you have. There may be aftermarket parts on the market but I cannot tell you if they will fix the problem you have.

If you’d like assistance with this, YourMechanic has mobile technicians readily available to diagnose your overheating issue and service your fan clutch if necessary. Best of luck.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

For what reason is my car grinding and forcing itself to turn off at low RPM's?

Hi there. The battery could be low on a charge. Check the voltage of the battery and if it's lower than 12.4 volts it will need to charged or replaced. for the grinding noise that you are hearing, either the...

Code C342D

Hi there. Either the throttle position sensor (TPS) or the idle air control valve (IAC) is not working. Check the wiring to the TPS sensor and the IAC valve and see if they are plugged in and if there is...

Loud clicking noise under dash sounds electrical. I just replaced cluster and it seems to be coming from somewhere else.

The clicking sound in the dashboard could be the hazard flasher energizing when the lights are not on. Also, there could be a sticking blend door motor that is skipping the gears and causing a loud clicking noise. If you...

Related articles

The Best Used Cars to Buy If You Need a Lot of Trunk Space
Many Many people focus more on interior room than cargo carrying capacity. That’s natural if you have a large family or regularly carpool, but what about drivers who need to carry a lot of stuff most of the time and...
Top Automotive News & Stories: October 1-7
BMW i5 images leak, an ultra-lux Jeep, hydrogen-fueled Colorado ZH2, Fisker's electric future, record plug-in sales, NHTSA Road to Zero, and more.
A Buyer’s Guide to the 2012 Chevrolet Sonic
The The 2012 Chevrolet Sonic is not only the only domestic subcompact sedan (or hatchback) on the market today, but it’s also one of the most versatile models in its class. This entry-level subcompact car – available in both sedan...