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HPCA & HPAA Systems

The HPCA and HPAA are designed to work in conjunction to control injection timing by altering injection housing pressure. Refer to Injection Housing Pump Timing Control chart to determine if system is functioning correctly.

INJECTION HOUSING PUMP TIMING CONTROL

Condition HPCA HPAA Housing Pressure: psi (kg/cm2 )
Low Alt. Package
Below 4000 Ft.
Engine Cold ON OFF 0
Engine Hot OFF OFF 10 (.7)
Above 4000 Ft.
Engine Cold ON OFF 0
Engine Hot ON ON 7 (.5)
High Alt. Package
Below 4000 Ft.
Engine Cold ON OFF 0
Engine Hot OFF ON 13 (.9)
Above 4000 Ft.
Engine Cold ON OFF 0
Engine Hot OFF OFF 10 (.7)