Pickup 2WD L4-155 2555cc 2.6L SOHC VIN E 2-bbl (1988)
Altitude Compensator: Testing and Inspection
Vacuum Switching Valve (VSV) - Federal Vehicles Only
Fig. 159 Testing the vacuum switching valve
1.
Remove the vacuum switching valve (VSV).
2.
Connect a hand vacuum pump to the black vacuum nipple of the VSV, Fig. 159.
3.
Apply 53 kPa (16 in. Hg) of vacuum and verify it is air tight.
4.
Blow lightly into the carburetor air bleed side nipple and verify that with 27 kPa (8 in. Hg) of vacuum air does not pass.
5.
Increase the vacuum to 34 kPa (10 in. Hg) and verify that air passes through the VSV.
