mystery noise

I have a weird news coming from what sounds like under my hood. it sounds like a fan propeller sputtering.I don't always hear it, at first I thought it might be the ac/ heat propeller behind the dash, but I'm thinking it can't be that, because I hear it, when I have the ac/ heat controls off.I always leave the setting on defrost/feet, but I hear it even when it's off.I opened the hood and looked, everything seems normal, I'm stumped! anybody have a clue?I have a 2013 4.0 v6 dclb, if that helps, thanx!

 

anybody?

 

Oh well, guess I'm the only one with this problem.

 

My 2009 DC has kinda loud ticking at lower rpm's, just figured these have noisy valvetrain.

 

it's not a ticking though, it's like a sputtering fan,I really don't know any other way to describe it.I thought it might be the cooling fan in front of the radiator, but, when I opened the hood with the engine running,I didn't notice anything weird, except maybe the hot pink on the fan,I mean,really? I only notice it when I'm stopped at a light, and its not all the time, if I'm moving,I don't hear it!

 

You say "I always leave the setting on defrost/feet" Doesn't that mean the air conditioning is cycling on and off?

 

I don't know,I don't think so,I could be wrong. Do you think it would matter?I actually meant defog/feet, sorry, not sure if it matters, I'm stumped!

 

Turn the dial to "vent" and see if it still makes that noise.

 

which one is vent? You mean the recycle button?

 

No. The dial to make air come out the vents toward your face.

 

does it happen when you drive your truck for the first time of the day and then stop not long after warming up fully because mine has a similar sound only when in the morning or when i first drive the truck for the day,it happens when i press the gass pedal or accelerate kinda heavy for the first 5 min on the way to work

 

no, it's not just the morning,I hear it in the morning and aftet I drove 70 miles home, it's not all the time, and, it's only when idiling at a light .

 

oh ok, I'll give that a try tomorrow, why ? do you think that would matter?

 

That is the hydraulic fan clutch..

 

On both defrost positions the truck runs the AC compressor. However if you turned the fan off the compressor would have shut off too.

 

OHHHH good to know hah thanks!!
Gotta love TW

 

I have noticed something similar on my 2012. Didn't hear it or notice until about 8000 miles. I can only hear it when say idle at lights. It sounds like a muffled low tone fast sputtering fan I guess. It will come on for about 15 seconds or more and then it will go away.

I don't notice at all times, and it will sound/appear at any point in the day/driving. It is too quiet to hear if driving, and you have to have the radio off or low. You can almost feel it in the seat. It as if a system/component is cycling/purging. First thought it was coming from behind the passenger rear seat, but now think it originates from in front of passenger under hood. No source found yet here either.

 

Exactly!!! Is it normal, or should I have it looked at?

 

is it normal?

 

bumpppp!