January 10, 2022
Chrysler 948TE, Honda/Acura, 9-speed and ZF9HP48 transmissions incorporate variable force solenoids to control clutch apply/release, torque converter clutch apply/release and line pressure. The solenoid pressure regulator valve insures proper flow volume and pressure to the solenoids during hot conditions and low pressure operation. Low feed pressure at idle can create delayed engagement or wrong gear starts. This valve also limits the maximum pressure to all the solenoids. Excessive solenoid feed pressure can flood the solenoids causing gear ratio codes, harsh up/downshifts and excessive line pressure. Reconditioning the bore and installing Sonnax oversized solenoid pressure regulator valve kit 85740-11K restores proper solenoid pressure regulation.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.