Century Estate Wagon V6-231 3.8L (1985)
OIL PRESSURE CHART
If the modulator is found to be functioning properly and the valve is not damaged, the shift problem is not vacuum related. At this time attach an oil
pressure gauge to the pressure tap as illustrated in figure 1. Note the pressures and refer to diagnosis section in the Service Manual.
As a reminder the T.V. cable does not control line pressure; it is used to control shift points (shift speed) only.
An updated oil pressure chart (figure 1) is attached which replaces the oil pressure chart in the Service Manual.
PRELIMINARY CHECK PROCEDURE
CHECK TRANSMISSION OIL LEVEL CHECK AND ADJUST T.V. CABLE
CHECK OUTSIDE MANUAL LINKAGE AND CORRECT CHECK ENGINE TUNE INSTALL OIL PRESSURE GAUGE CONNECT TACHOMETER TO ENGINE
CHECK OIL PRESSURES IN THE FOLLOWING MANNER:
Minimum Line Pressure Check With the brakes applied, take the line pressure readings in the ranges and at the engine r.p.m.'s indicated in the chart
below.
Full Line Pressure Check Full line pressure readings are obtained by removing the vacuum line from modulator, and with the brakes applied, take the
line pressure readings in the ranges and at the engine r.p.m.'s indicated in the chart below.
Line pressure is basically controlled by pump output and the pressure regulator valve. In addition, line pressure is boosted in Reverse, and Lo by the
reverse boost valve.
Also, in the Neutral, Drive and Reverse positions of the selector lever, the line pressure should increase with throttle opening because of the vacuum
modulator.
