wierd noise when using defrosters or AC

[jayyes]

when using a/c or defrosters with the heat on I am getting a weird pssst sound every minute or so it is coming from the passenger side engine compartment. I think it might be the a/c compressor clutch or the whole compressor the heat and the a/c both work fine if anyone has any input it would be appreciated if i put the heat on floor or vent it dosent make the noise

thanks.

[mytruckco]

I think the noise you are hearing is the a/c pumping through the condensor in your dash. It is a weird wooshing or gurgling sound. The reason you hear it with the a/c or defroster on is the a/c compressor is working during those times. If the heat is just floor or dash vents, i.e there is no defrost, then the a/c does not come on and you do not hear the noise. I though the noise was odd when i first bought my truck, as I had never heard it with any other vehicle I have owned. I even took it to the dealer, but they were able to show me what it was. Since then I have listended to several chevy trucks we have at work, and they all sound exactly the same.

[jayyes]

the only thing that bothers me is when it happens i get a hesitation or i should say loss of power also the noise just started the other day the noise you are talking about is different this is actually under the hood. it sounds like a loud tick with air being released .

[mytruckco]

Your right, that is definitely something else. Sorry I could not help!