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Home >> GMC >> 1998 >> Forward Control 7.4 J >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures - 7.4L >> Basic Fuel System Checks >> Fuel System Pressure Relief
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Fuel System Pressure Relief

CAUTION: Begin fuel system trouble shooting and diagnosis with checking fuel injection system pressure. High fuel pressure may be present in fuel lines and component parts. Relieve fuel pressure before disconnecting any fuel system components.
NOTE: For fuel pump circuit testing, FUEL SYSTEM ELECTRICAL CIRCUIT in NO START DIAGNOSIS .

Fuel system is under pressure. Pressure must be relieved prior to servicing fuel system. Fuel pressure may be relieved by using the following method: