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5.9L Only

  1. Using a vacuum pump, apply a constant 10 in. Hg of vacuum to Black side of delay valve. Connect one end of a 24 inch length section of vacuum hose to vacuum gauge, and the other end to colored side of delay valve.
  2. Observe the time in seconds for gauge pointer to move from zero (0) to 8 in. Hg. The minimum and maximum time for each valve type to reach 8 in. Hg is listed in FORWARD DELAY VALVE SPECIFICATIONS  . Replace delay valve if valve is not within specifications, otherwise install valve in its original position.
NOTE: When testing delay valve, prevent dirt or oil from entering valve.
FORWARD DELAY VALVE SPECIFICATIONS

Color of Valve Time in Seconds
Black/Gray 8-12
Black/Brown 16-24
Black/White 50-77
Black/Yellow 80-120
Black/Purple 3.2-4.8
Black/Green 160-240
Black/Orange 1.5-2.5