Check Engine Light With Code P1870: Buick Roadmaster Transmission & Drivetrain

Problem overview

The transmission may develop a harsh 1-2 shift and/or illumination of the Check Engine Light with code P1870 stored. This can be caused by wear of the bore for the TCC isolator and regulator valves in the valve body. This condition does not commonly occur until the transmission reaches normal operating temperature. If the valve body is worn, replacement will be necessary to correct this concern.

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Buick Roadmaster vehicles with this problem

1 model year affected

1996 Buick Roadmaster

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Check Engine Light With Code P1870 on Buick Roadmaster

Problem overview

Buick Roadmaster vehicles with this problem

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