Chevrolet Express 2500 Problem Report

Chevrolet Express 2500 Check Engine Light With Code P1870

(7 reports)

Vehicles equipped whit a 4 speed automatic 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.

Related Items:
One or both secondary air injection check valves may become restricted causing poor air flow re...
I hear a higher pitch whine coming from engine compartment.Only when in gear and get louder as...
My check engine light would sometimes come on in the winter. This last winter it did not. Now i...
Towing a trailer about 6000 pounds at high way speeds