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Diverter Valve - Diagnosis

S.L. 102C-4

11-9-78

SUBJECT:
DIVERTER VALVE DIAGNOSIS

VEHICLES:
ALL MODELS

GENERAL INFORMATION:

To check for proper operation of the diverter valve, use the following procedure:

^ Run engine to normal operating temperature.

^ Check tightness of the vacuum signal line connections at the intake manifold and the diverter valve.

^ Pinch the vacuum signal line at the diverter valve with vise-grips or equivalent.

^ Raise the engine RPM to :

1500-2000 RPM - 131 & 124 Spider Models
2000-2500 RPM - 128 & X1/9 Models

^ Put your finger nest to the diverter valve air discharge port. Open the signal line, checking if air is exhausted from the port. If there is no evidence of exhausted air at the discharge port, make sure that the vacuum signal line from the diverter valve to the intake manifold is not blocked.

^ If the signal line proves to be functional, then replace the diverter valve.