I'm not sure exactly what happened but I suspect a bad injector did it. He brought it to me a few months ago smoking white, I diagnosed it as a bad injector at the time. He came and picked it up before we really had a chance to dig into it and was going to bring it back when we could get to it. A few weeks ago it blew the gp harness out, we were swamped so he took it to ford. They said it was a bad injector and rocker arms, and tore it down to replace them. He called me told me what was going on and decided to have me repair it. When I got it they already had a new injector and rockers ready to install, so I never saw the old ones. I can't believe they were putting a new injector and rockers in a motor with a obvious compression loss and enough blow by the harness wouldn't stay in.