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For 1990-2009 cars only

Info - Cold Shift Pattern (Normal Condition)

Subject:Cold Shift Pattern (Normal Condition)

Models:1997-2001 Cadillac Catera
with Hydra-matic 4L30-E (RPO ML4)



Some owners of the above vehicles may comment on increased or higher engine speeds when the vehicle is driven immediately from a cold start. The Transmission Control Module (TCM) software contains a function that modifies shift speed speeds when the engine is cold. When activated, this feature will delay the shifts 10 to 15 km/h (6 to 9 mph), depending on the throttle angle.

The cold shift pattern enables if all of the following conditions exist:

    • The engine has been running for 5 seconds.
    • The engine temperature is between -40°C and +30°C (-40°F and +86°F).
    • Vehicle speed is 0 km/h (0 mph).

The cold shift pattern is disabled under any of the following conditions:

    • 60 seconds after activation.
    • If throttle angle exceeds 60.5 percent.
    • Vehicle speed exceeds 50 km/h (30 mph).

This is a normal condition, no repair should be attempted.