Lumina L4-151 2.5L (1991)
Fuel Pressure: Testing and Inspection
Fuel System Schematic
WARNING: To reduce the risk of fire and personal injury, it is necessary to relieve the fuel system pressure before connecting a fuel pressure
test. Refer to Fuel Pressure Release Procedure.
CAUTION
To reduce the risk of fire and personal injury:
1.
It is necessary to relieve fuel system pressure before connecting a fuel pressure gauge.
2.
A small amount of fuel may be released when disconnecting the fuel lines. Cover the fuel lines with a shop towel to catch any fuel leaking out.
Place the towel in an approved container once the lines are disconnected.
3.
DO NOT pinch or restrict nylon fuel lines to avoid severing. If nylon fuel lines become kinked, and cannot be straightened, they must be replaced.
4.
Wear safety glasses at all times.
FUEL PRESSURE TESTING
1.
Loosen fuel filler cap to relieve fuel tank pressure. (DO NOT tighten at this time.)
2.
Raise the vehicle to disconnect the fuel pump electrical connector, then lower the vehicle.
3.
Start and run the engine until the residual fuel is consumed. Engage starter for three seconds to assure fuel pressure relief.
4.
Disconnect the negative battery cable, and locate the fuel feed pressure line.
5.
Connect fuel pressure gage, J-29658-B, in between the fuel feed line and the TBI unit. Use the appropriate adapters.
6.
Raise the vehicle to connect the fuel pump electrical connector, then lower the vehicle.
7.
Connect the negative battery terminal.
8.
Perform fuel pressure checks.
9.
Relieve the fuel system pressure. See steps 2 and 3.
10.
Disconnect the negative battery terminal and remove fuel pressure gauge.
11.
Tighten fuel filler cap and connect the negative battery terminal.
12.
Cycle the ignition switch twice, waiting ten seconds between cycles. Check for fuel leaks.
