System Inspection
- During full throttle operation, float chamber temperature increases. This can cause fuel in float chamber to bubble and force its way out through the air vent tube and into the carburetor air stream. During secondary venturi vacuum, VCV system is activated to control float chamber pressure and prevent gas bubbling.
- Remove all hoses from vacuum control valve. See Fig 1
. Connect vacuum pump to port No. 1. Operate vacuum pump and verify passage between ports No. 2 and No. 3 opens at 1.57 in. Hg. Replace defective valve.
Courtesy of MAZDA MOTORS CORP.