Hate to say this since it isn't cheap, but a good GM dealership or
diagnostic shop that specializes in domestic vehicles could probably find
the exact problem in a few minutes. The time and expense you'd need to put
into it testing individual parts may make their services well worth the
cost.

"JURB6006" wrote in message
...

Anyway, I am familiar with how the modern fuel system works so I don't
need a
tutorial on it, what I need is specific info.