Tools Required

J 34730-1A Fuel Pressure Gage. See Special Tools and Equipment .

CAUTION: Remove the fuel tank cap and relieve the fuel system pressure before servicing the fuel system in order to reduce the risk of personal injury. After you relieve the fuel system pressure, a small amount of fuel may be released when servicing the fuel lines, the fuel injection pump, or the connections. In order to reduce the risk of personal injury, cover the fuel system components with a shop towel before disconnection. This will catch any fuel that may leak out. Place the towel in an approved container when the disconnection is complete.

Fig 1: Identifying Fuel Pressure Gauge J 34730-1A

Courtesy of GENERAL MOTORS CORP.

Turn the ignition OFF.

CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.

Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental attempt is made to start the engine.
Loosen the fuel filler cap in order to relieve the fuel tank vapor pressure.
Connect theJ 34730-1A or the equivalent to the fuel pressure connection.
Wrap a shop towel around the fitting while connecting the gage in order to avoid spillage.
Install the bleed hose of the gage into an approved container.
Open the valve on the gage in order to bleed the system pressure. The fuel connections are now safe for servicing.
Drain any fuel remaining in the gage into an approved container.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Fuel Pressure Relief Procedure

Use the Manual With the Right Hardware

When to See a Mechanic

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