Jump to content

Fans keep running after shutting off engine

Diverjer
 Share

Recommended Posts

Diverjer Enthusiast

Diverjer

Posted
Posted

Fans (both) keep running after shutting off engine even it this 35 degree weather.   This just started when driving home, notice a new noise and both fans were running.  All had been well and temp gauge was up normal and blowing warm air.   Shut off truck when got in garage and pulled out key and both fans still going, five minutes later they were still going.  

 

Found out if I start truck up, fans will stop running just for a few seconds and if I turn off key in that few seconds they won't come on.  Also noticed that temp gauge was sitting on cold as if not working.  It should be showing heat as it was driven for 30 minutes.  During start up heat gauge did do that thing of going all way up and then back down and stayed there on cold and fans start up.  So I have to start engine up then fans will stop and then quickly turn off truck to get fans to stop.

 

Any ideas, I would guess a heat sensor or something, but don't even know where one is located.   

 

This is a 2014 Silverado Work Truck, with 5.3 engine.  Bench seat, 2 door with 8 foot bed. 

rav3 Senior Enthusiast

rav3

Posted
Posted

How many miles on ur truck? Has the thermostat ever been changed? 1st I'd do is see if any of the radiator hoses were warm/hot. Do you have good heat from heater? Any codes?

Ur issue could be a number of things. No silver bullet without some diagnostics to start or you just start firing the parts cannon.

Diverjer Enthusiast

Diverjer

Posted
  • Author
Posted

Thermostat has not been changed, but hoses are warm and blowing lots of hot air.  Overflow is also a little warm.  Water is circulating.   Has 81,652 miles.   There isn't any check engine light, haven't found my code reader, moved a couple months ago everything a mess.   Would think check engine light would be on if any codes, but will try to find reader.  

rav3 Senior Enthusiast

rav3

Posted
Posted

Some codes are set without the CEL  being set. 

rav3 Senior Enthusiast

rav3

Posted
Posted

With what you've said, it appears your heating/cooling system is working. Next I'd look at your temp sensor.

Diverjer Enthusiast

Diverjer

Posted
  • Author
Posted

I watched they video and seems like what I have going on.  My temp gauge also is staying down and not moving up.  It was up until I starting hearing fans going and shutting off at home.   I don't know if my old 77 year old body can get up there and change that, will have to give a look.  The old lower back just don't like twisting around much. 

 

Thanks for the info.

rav3 Senior Enthusiast

rav3

Posted
Posted

I'm an old 77 year old Jarhead and I could do it on my Silverado. Doesn't take much to do. Just relieve the system coolant pressure before removing the Temp sensor but keep keep it sealed & coolant won't go everywhere like in the video.

Diverjer Enthusiast

Diverjer

Posted
  • Author
Posted

Think you are right, I did take off the electrical connection and put back on to see if bad connection.  That didn't help.  During the move we really downsized, from a 24 X 24 work shed on 5 acres to nothing but a garage and small house in a HOA- not my idea.  Got rid of lots of stuff and seems all deep well metric are gone, none of standard sockets seem to fit.   I was thinking same thing, release the pressure before removing sensor.   I may look around some more and find a socket?   My dad was a mechanic for Koss construction and I had a lot of his tool I finely got rid of and I bet all my metric stuff somehow got in with them.  

rav3 Senior Enthusiast

rav3

Posted
Posted (edited)

Go to the advance auto or autozone & they'll lone you what you need. Or just take to a service station with a mechanic & he'll change for you.

Edited by rav3
Diverjer Enthusiast

Diverjer

Posted
  • Author
Posted

I should have said, I thought I be smart and leave the sensor unhooked and that would stop the fan thing, that idea didn't work.  Fan still came on with sensor unhooked. 

rav3 Senior Enthusiast

rav3

Posted
Posted

I think I've helped as much as I can. Next is up to you. Semper Fi  

Honor Courage Commitment 

SDG

Improvise Adapt Overcome

  • Like 2
newdude Senior Enthusiast

newdude

Posted
Posted
3 hours ago, Diverjer said:

Fans (both) keep running after shutting off engine even it this 35 degree weather.   This just started when driving home, notice a new noise and both fans were running.  All had been well and temp gauge was up normal and blowing warm air.   Shut off truck when got in garage and pulled out key and both fans still going, five minutes later they were still going.  

 

Found out if I start truck up, fans will stop running just for a few seconds and if I turn off key in that few seconds they won't come on.  Also noticed that temp gauge was sitting on cold as if not working.  It should be showing heat as it was driven for 30 minutes.  During start up heat gauge did do that thing of going all way up and then back down and stayed there on cold and fans start up.  So I have to start engine up then fans will stop and then quickly turn off truck to get fans to stop.

 

Any ideas, I would guess a heat sensor or something, but don't even know where one is located.   

 

This is a 2014 Silverado Work Truck, with 5.3 engine.  Bench seat, 2 door with 8 foot bed. 

 

 

 

Its gonna come down to the coolant temp sensor or thermostat.  If you are getting heat, that tells me the thermostat is probably okay.  

 

Being its original and the problem these had 2014-2015 where the thermostat would over cycle and then cause the radiator to leak, if it were my truck I'd replace the thermostat and the sensor and change the coolant out if its original (Dexcool is 5yr or 150k mi, whichever comes first).  

Diverjer Enthusiast

Diverjer

Posted
  • Author
Posted

That sounds like a good suggestion, usually for whatever reason I would wait for 100,000 miles. 

 

Wonder if those fans would ever stop running, if I hadn't found that work around by starting up and quickly shutting off?  I guess they would stop when battery went dead.  That seems like a design problem, if key off electrical devices shouldn't be working. 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • Tyler Gibbs
      Travel Trailer 2024 2500 HD 6.6 Gas Engine ?

      By Tyler Gibbs · Posted

      The curb weight on a 1 ton crew cab long bed is around 7k lbs.  Now, I don't know where you went to school but 9k is not more than 2x 7k lbs. More than 2x 7k lbs would be 14k+.   With that said, obviously yes you're going to feel a 9k lb trailer when slowing down.  I already said, when accelerating.  When changing lanes?  No.  But if you look at the context of what was quoted, the original person said, "after a mile or two..." which means that would be after the accelerating portion and you're driving a generally steady pace.  Please do learn to read and comprehend.
    • sFrank
      2026 Silverado Range AFM DFM ECU loaction

      By sFrank · Posted

      So I purchased the Range unit for my 2026 and I am seeing different locations suggested for the ECM . Can anyone confirm wither under hood, left side or right side or behind the wheelwell?
    • No F-bdy Bs
      Dave's Auto (custom engine builder) tear down of L8T

      By No F-bdy Bs · Posted

      Like I've said before. Di and Carbon buildup is not that big of a concern. Engine had minimal buildup, and that engine was obviously not super well maintained. Do regular oil changes, and you're gtg as long as the rest of the truck lasts. Also, the High Pressure FP that people ****** about, but can't tell you why.  Now, I wish they'd trash the variable oil pump. No real world issues with them, but I'll gladly eat whatever miniscule MPG it's saving me in favor of more oil at all RPMs.    Curious to see his assessment of the 7.3 compared to the 6.6. I expect he'll praise the port inj, but from a structural standpoint, the 6.6 is as robust as any engine out there.    Not to take away from the 7.3. I feel it's equally as good as the 6.6.     As to heat on the rear cyls, I'd have to see numerous examples before I'd say it's an issue. Especially not knowing the history of that engine. For all is known, they could have blown a rad hose, and ran it hot, and the 2 rear cyls may be the first to get hot in a low coolant situation, but not be an issue aside from that. 
    • Donstar
      Navigating senior years.

      By Donstar · Posted

      "Life is getting back to normal."    I'm driving again and all new joints are operating as expected for this stage of recovery.   My most recent joint replacement still requires a lot of attention but experience has taught me that time will quiet the remaining pain.  I joked with my surgeon that another joint replacement would take my mind off my most recent surgery and he responded by saying the next will be a hip!  There are no plans for another surgery but, unlike me, I don't think he was joking!  I certainly wouldn't refuse further replacement  if required but hope to spend time out of the "post-op"  period.  I can't stress enough that if you have been recommended for total hip, knee or shoulder replacement that you welcome the offer.  Post-op "recovery" may sound daunting and painful, however, this is far better than the insidious erosion of mobility you are currently experiencing.  Imagine what it would feel like to wake up most mornings feeling better and more mobile than you did the previous day!  Prior to my first surgery in June 2025, even getting out of bed was becoming a formidable task.  Since the day after my first surgery, I get out of bed everyday easily and unassisted.  Making the switch to feeling a little better each day rather than a little worse, is hugely motivating!
    • Coastie05
      ‘25 Silverado purchase- back to dealership for bumper/radio issue

      By Coastie05 · Posted

      Hope it all works out for you. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...