99 LS400 Air in PS fluid
04-12-17, 02:16 PM
#1
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99 LS400 Air in PS fluid
Recently noticed bubbles in the PS fluid of my 99 LS400. As the system "growls" a bit when turning the wheel side to side. Sounds like air leak in the system somewhere. Does anyone have a good overview on this (pics) as how to fix and what to replace??
Bruce
Bruce
04-13-17, 08:09 AM
#2
I've recently replaced my ps pump and re-bled it. If I remember correctly you will have some bubbles in it when it's running. Minor stuff, not overflowing. You need to bleed it properly by lifting the front end and turning the wheels from side to side multiple times. Also, don't put power steering fluid in it. Clearly on the lid it states Dexron transmission fluid. It will not work for long on PS fluid. Due to pressure build in the system to make it work, you're more likely to have fluid leaking out than air leaking in.
Have you changed the fluid recently? That can help the operation.
Have you changed the fluid recently? That can help the operation.
04-13-17, 11:30 AM
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Have not replaced it, just noticed it was low and that it had bubbles in it. So my guess is that it is leaking and trying to find out why/where and what needs done...
Bruce
Bruce
04-14-17, 03:48 AM
#4
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How many miles on your car...?
Volumes have been written on this forum re the infamous PS / IAC valve. The idle air control valve eventually fails which drips PS fluid into the intake plenum causing smoke at start up. Replace the PS pump with a Lexus part. Yes it's expensive but aftermarket rebuilt pumps will fail sooner than later. Spend money now or spend money a second or third time. Ask me how I know...? I've only driven these cars since 1998!
Volumes have been written on this forum re the infamous PS / IAC valve. The idle air control valve eventually fails which drips PS fluid into the intake plenum causing smoke at start up. Replace the PS pump with a Lexus part. Yes it's expensive but aftermarket rebuilt pumps will fail sooner than later. Spend money now or spend money a second or third time. Ask me how I know...? I've only driven these cars since 1998!
04-14-17, 11:59 AM
#6
Lead Lap
before this gets out of hand, let me just clarify that on the 1998-2000 LS there is NO idle air control valve... in 1998 the throttle control changed to electric control and the position of the throttle valve is just controlled by this and not an additional IAC valve. there's a chance that the rack itself has some internal leak in it, that's what mine is dealing with right now and it makes the same whining sound. for now i'd probably just recommend pouring some lucas stop leak into the reservoir and let that work its way into the system before throwing any new parts at it
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