Porsche 928 Workshop Manual page 1254

92s Differential, Transaxle System
39
Checking pilot pressure valve of lock hydraulics (lock operation)
General
Normally the pilot pressure valve is checked within the scope of measuring the friction coefficient of
the transverse lock (test item 3).
A pilot pressure valve (arrow) is located ahead of the transverse lock slave cylinder on the left-hand
transmission side.
If pilot pressure is too high, squeal noises may result. Due to wear and vehicle dynamics constraints,
zero pilot pressure is also to be avoided. When replacing components, do not confuse with the
PDAS pilot pressure valves designated for the 911 Carrera 4.
Specifications / identification of the pilot pressure valves
Type
911 Carrera 4
929 with PSD
Specification Identification
I
~
approx. 2.0 to 3.5 bar
2
3 stamped on valve
~
approx.
3.0 to 4.5 bar
3 - 4 stamped on valve
PSD-Diagnosis I Troubleshooting
Printed in Germany - XXVII, 1991
039 - 215