May 21, 2013
Debris and constant oscillation of the converter clutch regulator valve can create scratches on the critical valve spools, allowing valuable regulated line pressure to leak and setting 628 and 1741 codes. Excessive spool scratches also make the valve unsuitable for use with Sonnax TCC regulator sleeve kit 37947-09K. Sonnax direct replacement TCC regulator valve 37947-38 may be used in the original casting bore or with the Sonnax 37947-09K sleeve when the bore cannot be salvaged with an OE-diameter valve.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.