I'm hearing a strange noise coming from somewhere around the engine.. I notice on an initial cold start while warming up a popping sound in the engine bay..It doesn't sound like a backfire but a muffled pop.. Also when i'm slowing down to a stop and let off the gas I hear a weird noise like somethings rubbing against something... It does it for like 4 or 5 seconds and stops.. Both noises are on the driver's side near the CAI.. If anyone has a clue please give me some insights.. I have been having power loss issues for a long time and this has been the most recent thing i've noticed. When I quickly depress the gas pedal I get poor response from the truck.. I'm not throwing any codes or having any major idling problems

Thanks

 

Dare i say it, start looking for a loose plug today!

 

Check your lower pulley, maybee it needs to be re tightened.