GM Full-Size Trucks 1980-1987 Repair Guide

Relieving Fuel System Pressure


The pressure regulator utilizes a constant bleed feature when the engine is turned OFF, but follow these general tips:

  1. Always disconnect the negative battery terminal.
  3. Loosen the fuel filler cap to relive the vapor pressure in the fuel tank.

The 220 TBI Unit introduced in 1986 has a bleed in the pressure regulator to relieve pressure any time the engine is turned off, however a small amount of fuel may be released when the fuel line is disconnected. Keep a rag handy to soak up any gasoline that might spill on any other components. Immediately dispose of the rag in a container approved for flammable or combustible refuse.

Click image to see an enlarged view

Fig. Fig. 1: Cross sectional view of the TBI 220 operation