My truck seems to be losing power. Takes forever to get up to speed on highway. on 1996 Chevrolet S10

REALLY bogs down on hills
Fuel pump replaced on 5/22 along with fuel filter and several inches of fuel line on either side.
Diagnostic machine at O'Reilly's said that the system was "too rich"

Asked by for the 1996 Chevrolet S10
2 answers 2 comments
that means its running rich ck fuel trim and fuel delivery issues you may have stuck open injector
How would I know which one to replace? One at a time trial and error?
get a proper diag
Don't guess, have it tested by a qualified tech. Unless you have money to waste.