I was wondering if i could get a little help with an issue I've noticed on a 2003 GMC Sonoma SLS 4x2 with the 4.3L V6. Basically, its a slight hesitation that occurs while driving at any speed (only noticed it at 55+ MPH), and it seems to happen one out of ten times when the vehicle is nice and warm. Odd thing is, even when you notice it, its not a constant hesitation that continues to happen when you get that one time it decides to show its self. Also, when it hesitates there is kind of like a metalic squeak, kind of like metal rubbing on metal. Almost reminds me of the knock my 1999 GMC Suburban has... This started happening about 3000 miles since I did plugs and wires. Prior to that it was great. Could this be engine knock that is being caused by the new plugs?