Engine hissing noise
Hello,
I have a 01 GMC Sierra 2500 with the 8.1 liter V8. Did some driving in 90
degree weather, After shutting the engine off I heard a hissing sound coming
from the engine for a few seconds after shutting the motor of. AC was running
while I was driving no problems with overheating engine temp is normal didn’t
see any leaking coming from the engine bay or under the motor. Heating and
cooling work fine. Low mile motor with 47,000 original miles.
Wanting to make sure this is normal and not something worry about having
looked at thanks.