Everytime I turn on the A/C in my truck I hear a loud "clunk" noise and the truck hesitates or bucks for a second. After this noise it takes off again fine and everything runs great the rest of the ride. The A/C works fine after this initial noise and engine hesitation.

Does anyone have any idea what this could be or what should be done to fix it?

Thanks in advance for any help!

 

Sounds like the compressor clutch engaging. If it's engaging harshly though, the system may have a slightly low charge or there may be some moisture and/or air in the refrigerant.

 

So is this something I should have checked out or will it not harm anything?

 

Clutch also might be sticking along with low refrigerant might be able to add some AC oil, might ease the problem.

 

Thanks smkeater,
By adding AC oil, do you mean adding some more refrigerant?


If so I guess that means another trip to the shop.

 

Some of the newer refrigerent cans have the oil mixed in. Its been awhile since I worked on AC's they used to sell just the oil additive. Just make sure you dont over pressure your system..

 

Looks like I will be making another trip to a shop since I don't know enough about the A/C system to work on it. Thanks for the info!