2000 LS2 v6 fuel problem?

Measure the fuel pressure under load and see what you get. Duct tape the
pressure gauge to the windshield.
btw - an old R12 refrigerant manifold gauge set is now worthless (unless you
have an EPA license). It just happens to fit the fuel pressure test port. I
use the low side gauge as 49psi is the target pressure.
You might also have to do a flow test to see if the problem is in a crushed
fuel line or something wrong in the fuel pressure regulator. On that last
one, make sure that the vacuum line from the intake plenum to the fuel
pressure regualtor is intact.

I've been going through all this on my 2001 lw300 getting a 'lean bank 1'
and 'lean bank 2'. Upstream O2 sensors read 1V (rich) and downstream sensors
read .7V (normal). Long term fuel trims are high. Points to a low fuel
pressure (dead-on at 49 psi) or vacuum leak but I haven't found one yet.
Thankfully, the friendly local service shop (not Saturn) lends me their
Snap-On diagnostic scanner.

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