^ Link does not work.Thanks, Rob

Rob,

Does the backfiring and power loss happen right about 0psi? If you rev it slowly/easily, how high can you get the revs before it starts going crazy?

It could be a bad secondary injector (not opening or disconnected), it would have very similar symptoms. Something could also be triggering "limp home mode." When I'd pass 0psi my car would act like that, I had a bad wire to the oil metering pump. However, a code would show up, so that's likely not your problem. I didn't get a code when one of my secondary injectors wasn't connected.

Wade