Strange Noise at Start-up

[Plimbob]

My 07 (234,000 miles) has developed a strange noise about 10-15 seconds after cold start-up - overnight. It sounds like a creaking door coming from the engine compartment and is plenty loud enough to hear in the interior. The noise last about 5-10 seconds and then quits. I turned the AC off and no effect.

Any thoughts?

 

[Doubeleive]

video? if you are unable to pinpoint it, I would maybe start by taking off the serpentine belt, then it's just the engine and AC, if the sound is gone then try spinning the alternator or steering pulleys by hand and see if they make any noise.

 

[swathdiver]

Not an AC door behind the dash?

 

[iamdub]

Autolevel compressor on the fritz?

 

[Plimbob]

Autolevel compressor on the fritz?

 

[Plimbob]

I haven't had a chance yet to remove the belt but I popped the hood and had my wife start it and it sounds and feels (vibration) like it's coming from the passengers side and more toward front area?

 

[Doubeleive]

I haven't had a chance yet to remove the belt but I popped the hood and had my wife start it and it sounds and feels (vibration) like it's coming from the passengers side and more toward front area?

could be the ac compressor that's about the only thing in that area that would make strange noises, you could take that belt off also and see if the noise goes away.

 

[Plimbob]

Update - I am fairly sure it's the AC compressor, when the AC is off at start-up it doesn't make the noise. I was going to add some AC lubricant to the Freon to see if that improved things? I assume this is the beginning of the end of the compressor?

 

[iamdub]

I wouldn't add anything to the Freon. All that should be in the system is a special oil and the refrigerant (Freon) and it should never leak out because the system stays completely sealed. If the noise is indeed coming from the compressor, I'd bet it's the clutch. You can replace the clutch without opening up the system. It's about a 30-minute, $100 bolt-on job.