A few weeks ago my 5.3 started misfiring during acceleration or when a load is placed on it. It idles just fine with no issues. With 140K miles I decided a complete tune up was in order. I replaced all plugs, wires and all 8 coils with good quality OEM parts. The plugs and wires only had 40K on them but I decided to replace them anyways. After all that it's still misfiring. The computer hasn't picked up on it as it has not thrown any error codes and the check engine light hasn't come on. All 8 spark plugs look exactly like this. The center electrode is almost gone, its now smooth causing the gap to double in size. They only had 40K on them. Any ideas what would cause the misfire to continue? Any ideas as to why my plugs look like this? Are the problems related? Appreciate any insight.
.jpg.8de1304a72cfb3366153a6c2e93b2277.jpg)
