The Series 60G automotive GT42 turbocharger requires a boost recirculation valve to reduce air system pressure pulsations and turbocharger surging during engine throttling operations. The recirculation valve is remote-mounted by the OEM and routes air from the high-pressure boost side back to the air inlet side during deceleration. The recirculation valve is a large solenoid valve that is triggered to open by DDEC through a digital output pin of the ECM. See Figure 35341 for recirculation valve.
The recirculation valve isa non-serviceable component and should be replaced as a unit. No adjustment is required.
Remove the recurculation valve as follows:
Note: The valve has a mounting bracket attached to its body. Do not remove the bolts in the valve body to gain access to the valve. Removal of these bolts can expose the valve diaphragm and cause permanent damage.
Install the recirculation valve as follows:
Note: Ensure the arrow on the base of the valve corresponds with the flow of air from the turbo outlet side to the turbo inlet side.