Fuel Injector Balance Test
WARNING: This page is about a different car, the 1996 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
Connect Tech 1 scan tool and select "Inj. Balance" test. Start engine. Record change in engine speed and idle quality as each cylinder is disabled. Engine speed and idle quality changes should be equal for all cylinders. If changes are not equal, check ignition system or perform further diagnostics. See TESTS W/O CODES or TESTS W/CODES article.
CAUTION:
To avoid possible vehicle fire, wrap shop towel around fitting to absorb fuel spillage.