Arkansas89Chevy
Newbie
Recently put new AC compressor, drier, expansion valve, o-rings, pressure switch, etc. on the truck. Best I can describe the noise is a "moan" under the hood at a very specific rpm ONLY when the AC is running. Truck does not have a tach, but it happens around 25 mph, and is worse when i'm coasting. I can slightly press the gas pedal to make it go away. It's almost like something is vibrating under the hood at a certain rpm/frequency. I've checked for loose brackets, etc. till i'm blue in the face. And it's odd that it only does it when running the AC. Anyone experienced this or have any ideas?