A while ago there was a discussion involving fuel additives and the corrosive "cleaning agents" used to keep injectors and valves clean. I was having a string of injector failures and all I'd fill up on was Chevron with Techron. After finally switching out injectors I did some research and started using shell and 76 and haven't had an injector problem since... Now I'm not saying this is definitive...certainly one case in a string of a couple may mean nothing...but its nice having working injectors and all I've done is change fuels...give it a shot...may work.