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A/T - Cycling Between 2-3 When Speed Levels Off


SIL 89-15 (Apr)

SUBJECT: SPRINT SERIES

PROBLEM:
After the first upshift pattern, continuous cycling occurs between second and third gear when speed levels off.

CAUSE:




There are three vacuum controlled switches which are housed in a metal box mounted on the firewall. Manifold vacuum closes the contacts of each switch at given vacuum ranges (See Figure 1). The vacuum switches control the off/on sequence of the shift solenoid (See Figure 2).

SOLUTION:
Remove housing cover. If transmission then functions correctly, look for crimped vacuum line inside housing.