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I have a 2004 Chevy Silverado with the 4.8. The truck has recently been flashing the check engine light when accelerating. I checked the codes and it is showing a po307 and po332. I already replaced the plugs and wires. I also tried a new coil pack on the #7 cylinder. Although all of that seemed to help bring some power back, I’m still getting the 307 code. The truck also hesitates and makes a loud popping sound when under load or hard accelerating. Will replacing the knock sensors fix this? Any help on where to go next before I dump more money into it would be much appreciated.
 

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Maybe pull the valve covers and check the rocker arm action and/or do a compression check. I had similar symptoms with a Chevy 305 years ago. It turned out to be the lobes on the cam were worn and I was getting almost no valve lift. (Out of warranty but Chevy reimbursed me for the parts.)
 
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