1990 LS400 PS pump redux

[Jerohm]

Still playing around with this issue. I had a Chicago independent shop
install a salvage pump back in January. Well there was a minor connection
leak. I live in CT and am back in Chicago this week. Well they said they
fixed the leak (only just picked up the car today, so ...?!?), but there is
a "new" issue. When I first start the car, the PS assist (level) is EXACTLY
as before (GOOD), but after a minute or two, the assist level is stiffer
than it used to be. This condition is repeated every time after the car is
stopped (off) and restarted at a later time. The PS is definitely working
... just stiffer. Any insight?

Thanks as always.

[Jerohm]

Post by Jerohm
Still playing around with this issue. I had a Chicago independent shop
install a salvage pump back in January. Well there was a minor connection
leak. I live in CT and am back in Chicago this week. Well they said they
fixed the leak (only just picked up the car today, so ...?!?), but there
is a "new" issue. When I first start the car, the PS assist (level) is
EXACTLY as before (GOOD), but after a minute or two, the assist level is
stiffer than it used to be. This condition is repeated every time after
the car is stopped (off) and restarted at a later time. The PS is
definitely working ... just stiffer. Any insight?
Thanks as always.

I played around a little more, and I am convinced that the stiffening
doesn't happen until I actually drive the car. If I start the car, and turn
the steering wheel from one side to the other, the "play" is the way it
always WAS. As SOON as I put the car into drive and move it, the steering
stiffens up. ... any ideas??

[Ray O]

Post by Jerohm

Post by Jerohm
Still playing around with this issue. I had a Chicago independent shop
install a salvage pump back in January. Well there was a minor
connection leak. I live in CT and am back in Chicago this week. Well
they said they fixed the leak (only just picked up the car today, so
...?!?), but there is a "new" issue. When I first start the car, the PS
assist (level) is EXACTLY as before (GOOD), but after a minute or two,
the assist level is stiffer than it used to be. This condition is
repeated every time after the car is stopped (off) and restarted at a
later time. The PS is definitely working ... just stiffer. Any insight?
Thanks as always.

I played around a little more, and I am convinced that the stiffening
doesn't happen until I actually drive the car. If I start the car, and
turn the steering wheel from one side to the other, the "play" is the way
it always WAS. As SOON as I put the car into drive and move it, the
steering stiffens up. ... any ideas??

There are basically two types of variable assist PS systems. The most
common is where assist is reduced at higher engine RPM, and the power
steering pump provides less assist as it spins faster.

The other type is where a speed sensor feeds a computer that controls a
valve in the PS system to reduce assist. I believe this is the type in your
car. Look for any disconnected or damaged wires in the vicinity of the PS
pump or wherever the leak was.