P0300 and hesitation going up hills

[somguyss]

I ran into same issue on a 2010 GMC Denali 6.2 liter, after trying plugs and a good BG Fuel Service i went back and started thinking that only things that can cause a P0300 Random Mis Fire was going to be fuel or air management after doing some testing with scanner i determined it wasn't a air management issue so no MAF or O2 issue i started looking towards fuel and found that at times my fuel pump was dropping regulated pressure, 145000 miles you wouldn't have thought would have been issue but that was exactly what the issue was.

I have also seen sometimes poor plug wires cause a random misfire at times.

 

[RAFJR]

I ran into same issue on a 2010 GMC Denali 6.2 liter, after trying plugs and a good BG Fuel Service i went back and started thinking that only things that can cause a P0300 Random Mis Fire was going to be fuel or air management after doing some testing with scanner i determined it wasn't a air management issue so no MAF or O2 issue i started looking towards fuel and found that at times my fuel pump was dropping regulated pressure, 145000 miles you wouldn't have thought would have been issue but that was exactly what the issue was.

I have also seen sometimes poor plug wires cause a random misfire at times.

..and so you replaced the fuel pump??

 

[somguyss]

..and so you replaced the fuel pump??

yes replaced the fuel pump and all was good then had 2 DOD lifters go down so DOD delete it was.