The fan revs high occasionally when the vehicle runs for a while?

2006 GMC ENVOY
205,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
Avatar
SHANNON454545
  • MEMBER
  • 4 POSTS
The fan on the motor revs high and makes a pound revving sound sometimes when the vehicle runs for a while, but it seems to only do it when it's hot outside. I get the error code from the check engine light P0 something and it says it could be fan speed sensor.
Sep 18, 2023 at 6:36 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Hi,

The radiator cooling fan on this vehicle does have some electronics. If you have the code you retrieved, let me know what it is so I can research it.

The electro-viscous (EV) fan clutch is controlled by the vehicle PCM based on temperature and need. If the fan recognizes the under-hood temperature is at a specified threshold, the PCM will cause the fan to turn faster. (See fan below)

If you experience the jet-like sound only when it is hot and the vehicle is sitting idle, that really isn't odd. It is expected.

So, I need to know what the code is so I can read through it and make a determination. Also, if the noise slows or stops when the vehicle begins to move, what you are experiencing may be normal.

Let me know.

Take care,

Joe

See pic below.
Image (Click to enlarge)
Attached Media
Sep 18, 2023 at 8:11 PM
Avatar
SHANNON454545
  • MEMBER
  • 4 POSTS
The code is P0526.
Sep 18, 2023 at 9:23 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Hi,

Thanks. The code indicates the powertrain control module loses the fan speed signal for a specific amount of time. It could be the result of the fan clutch, a wiring issue, a connector issue, and so on.

If you look below, I attached the diagnostics for this code. Take a look through them and let me know if you are comfortable performing them

Let me know,

Joe

See pics below.
Images (Click to enlarge)
Attached Media
Attached Media
Attached Media
Sep 19, 2023 at 8:00 PM