BP has a claim system in place. They were pretty quick in setting things up, but I don't think they realized the size of the problem. I have already provided the estimate for the bad fuel related costs, and we are just waiting for a response to the claim. My research in regards to the symptoms caused by the BP gas has only provided vauge answers. Apparently, the damages have varied from just a tank and fuel system flush to an entire fuel system job (injectors, pump, filters, regulator, etc.).
The car was already knocking on cold startup before it came into the shop. It became much louder and constant after the service. The customer didn't mention the prior knock until after I called him post-service. Likewise, he did not inform me of the BP gas until later.
I don't believe I did anything wrong during the service that caused the knocking problem. Like I said, the only thing that could have made its way into the engine was the anti-ratte parts inside the upper plenum. Everything else was accounted for, and the lower intake was cleaned out before the upper was reinstalled.
I found the bulletin after the service while trying to diagnose the cause of the knocking sound. If I had found it before hand, I would have approached the job differently and probably would have refused it. If parts can come loose inside the intake plenum just as a result of tipping it aside during a simple tuneup, that's a headache I don't want to deal with again. Too easy for the worst to happen.
Spence's post about "let BP pay for they problem and the customer for theirs" makes sense because they are unrelated problems. The intake issue presented itself only after fufilling the customer's request to service the vehicle. It may have occured on it's own after driving over a rough set of railroad tracks... or it may have never happened for years. That's something everyone involved can only speculate on.
I already took the "extra mile" approach and offered to "eat" the labor on the repairs related to the bulletin. The customer is still happy with us so far. My only fear is that the cost of the parts will be greater than what he can afford, and that may encourage him to change his attitude and try to blame me for the problems in an effort to get his car fixed. Not that his financial problem is really my problem, but I still feel empathy for him, and also want to avoid a lawsuit or insurance claim. But, with business being already slow, a "freebie" is impossible.