mig25 Posted July 31, 2003 Share Posted July 31, 2003 There is a little vacuum valve attached to the power steering reservoir. What does it do? My one went bad and the engine was burning Power Steering fluid. I removed the two vacuum hoses and plugged the little niples. The engine does not smoke anymore and the Power Steering fluid does not go down. But I wonder what is the function of the valve... Quote Link to comment Share on other sites More sharing options...
VBdenny Posted July 31, 2003 Share Posted July 31, 2003 Don't ya just love stuff like that? Somebody on the forum said it had something to do with the steering effort or something I thought. Wouldn't you just love a junkyard full of Lexuses? I go to the junkyards all the time and all I've ever seen is a couple of 90 ES250's I did try to disassemble some stuff to learn. Better than Busch Gardens for me. Quote Link to comment Share on other sites More sharing options...
VMF Posted July 31, 2003 Share Posted July 31, 2003 lucky you... They dont let you in here in new york, you have to order part through the mecanic who has connections, and they will deleiver the part. but no self dissasembling.... i would love that too. but most of all i wanna go to mojave to walk around those big dead planes..... he he Quote Link to comment Share on other sites More sharing options...
VBdenny Posted July 31, 2003 Share Posted July 31, 2003 There are at least 25 junkyards within 25 miles of me. I often spend a day just roaming around looking at stuff. Call me wierd, but I'd rather spend a day at a junkyard, than at an Amusement park. We have this new place called U-Wrench-It. Costs you a buck to get in (an yes, some people B about the buck). All of the cars are seprated by make and set up on blocks so you can get underneath. The stuff is really cheap, they even provide wheelbarrows to haul stuff around. You get a 30 warrenty on parts for an exchange. Space is rather Ltd. in NYC so I'm not surprized. Unfortunetly (or maybe not) there are not many Lexuses ever in the boneyards. Sounds better than Great Adventures huh. Anyway, with all the stuff you do, you should qualify as a maechanic seeing as you probably know more than most of them. I can't recall ever seeing a junkyard in B'klyn. Quote Link to comment Share on other sites More sharing options...
jzz30 Posted July 31, 2003 Share Posted July 31, 2003 it keeps steering effort at a constant even when the pump rpm varies. and you should change that. Quote Link to comment Share on other sites More sharing options...
Rich Sweitzer Posted July 31, 2003 Share Posted July 31, 2003 jzz30 is quite correct about the boost. The device is a pressure-operated air valve. The way it works is at elevated PS pressure (such as you would have during a very sharp turn) the valve opens. One of the hoses attached to it is tapped off the air intake after the filter, but before the throttle. The other hose taps in after the throttle. The effect of all this is to allow a small amount of bleed air around the throttle when the PS pressure is elevated. That in turn boosts engine speed slightly (if it's running at relatively low RPMs) to compensate for the increased load on the engine. Quote Link to comment Share on other sites More sharing options...
thewzdoc Posted August 1, 2003 Share Posted August 1, 2003 The hose that runs from the bottom of the reservoir to the front of the air plenum slipped off the reservoir. The car ran fine while the engine was at cruising speed but at idle it would jerk and act like it was going to die. I stuck the hose back on and it’s been running fine. I noticed that the hose was wet with PS fluid. Where is the valve at? Is it in the reservoir? Quote Link to comment Share on other sites More sharing options...
mig25 Posted August 1, 2003 Author Share Posted August 1, 2003 The reservor has a little valve attached to it, with two little hoses that goes from the valve to the Intake hose and the other one goes to the front of thee intake manifold Quote Link to comment Share on other sites More sharing options...
thewzdoc Posted August 1, 2003 Share Posted August 1, 2003 Hmmm..I don't remember a valve only a metal tube that appeared to be welded to the reservoir. I'll ook again when I get home. Quote Link to comment Share on other sites More sharing options...
mig25 Posted August 12, 2003 Author Share Posted August 12, 2003 Bellow that, actually the valve is below the reservoir Quote Link to comment Share on other sites More sharing options...
Rich Sweitzer Posted August 13, 2003 Share Posted August 13, 2003 Correct, the valve is actually screwed into the power steering pump below the reservior, and it taps into the pressure side (as opposed to the return side) of the pump. Quote Link to comment Share on other sites More sharing options...
mig25 Posted August 13, 2003 Author Share Posted August 13, 2003 :D FIXED IT !! REPLACED THE VALVE. LOOKS AWESOME, DOES NOT LEAK AND THE CAR DOES NOT SMOKE ANYMORE ! :D It was quite a work to do, I had to remove the high pressure side of the power steering to get to the valve itself. It is all done from the bottom of the car. It takes a 17mm open end wrench. I went ahead and flushed the power steering system,and replaced the ATF welgaby@msn.com Quote Link to comment Share on other sites More sharing options...
prento Posted August 16, 2003 Share Posted August 16, 2003 You Guys saved my !Removed!. I have a 91 LS400. lately, it started losing PS fluid a few weeks now, then it started smoking. I noticed the smoke was whitish and odorless, So I ruled out burning oil. I also noticed that the PS fluid was going no- where either, not on the ground nor under the car. Also, the oil level was not going down. I was too dumb and too busy to connect the dots. Took it to a mechanic, he tells me I need a head job, my valve seals are bad. I knew that was bull. Now that I've read this post, I think I know the problem. Quote Link to comment Share on other sites More sharing options...
JPI Posted August 16, 2003 Share Posted August 16, 2003 Instead of buying a new one I can rebuilb this unit for half of the price. JPI Quote Link to comment Share on other sites More sharing options...
drg1cfo Posted April 7, 2008 Share Posted April 7, 2008 The hose that runs from the bottom of the reservoir to the front of the air plenum slipped off the reservoir. The car ran fine while the engine was at cruising speed but at idle it would jerk and act like it was going to die. I stuck the hose back on and it’s been running fine.I noticed that the hose was wet with PS fluid. Where is the valve at? Is it in the reservoir? The valve is threaded on side of power steering pump Quote Link to comment Share on other sites More sharing options...
TexasLexus94 Posted April 7, 2008 Share Posted April 7, 2008 I'd just like to add that Rich Sweitzer must be one of those Teutonic types who really understand mechanical stuff. I replaced the ACV on my P/S pump because I was continually filling the reservoir a couple of years ago, and had no clue why the valve needed to be replaced, and what it actually did. Now I know. Thanks, Rich. Quote Link to comment Share on other sites More sharing options...
90LS400Lexus Posted April 7, 2008 Share Posted April 7, 2008 Since he asked that question in 2003, hopefully he has already figured it out and replaced it. ;) :D Nice for future reference though... thanks for the info! Welcome to the forums too! The hose that runs from the bottom of the reservoir to the front of the air plenum slipped off the reservoir. The car ran fine while the engine was at cruising speed but at idle it would jerk and act like it was going to die. I stuck the hose back on and it’s been running fine.I noticed that the hose was wet with PS fluid. Where is the valve at? Is it in the reservoir? The valve is threaded on side of power steering pump Quote Link to comment Share on other sites More sharing options...
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