Trying to figure out which cylinder is #3 on this 2000 Suburban (5.3L).

Getting these 2 codes -- P0303 and P0101.

Would like to read this specific #3 plug before tackling the MAF code. I have reason to believe that there is a head gasket leak.

 

#3 is second plug back on the driver's side. 1, 3, 5, & 7 on left side and 2, 4, 6, & 8 on right side.

 

Where did you go to get it flashed and what is it called? I think I need it for mine... thanks