Neofate

iTrader: (1)

Hey guys,

Just replaced the power steering pump and reservoir.

The Rack and Pinion has been replaced as well.

No more pulley wobble, no more noise.

However,.. *Randomly* -- At idle when not moving, the power steering just goes out. It is very hard to turn the wheels, as if the power steering was not doing anything. Although sometimes (only tested it on the drive home) -- when coming to a stop it will work fine.


***Note at speed the power steering works very flawlessly/smoothly****


So when I got in my driveway, and stopped, it was very hard to turn at idle. I put it in neutral and revved it up .. As I revved the engine the power steering would work smooth again,.. let it fall back down to idle.. very tough.

So all that is left is the Air control valve.

This how a bad Air control valve would react? Work sometimes, sometimes not? Get your rpms up a little and everything function properly?

If so, then I know that is where to go to next --

Also, there is cheap fix, plug , for this Air control valve. If I plug this thing will the power steering work at idle? Will it be tough like it is now to turn the wheels? Or plugging it still make it work to some degree at idle so I can turn the wheels without really putting muscle into it. (Be fairly tough on a small female driver).

Thanks for the input.

Keep in mind, New Rack and Pinion, Cleaned Solenoid Screen, Flushed Twice, Brand new Power Steering Pump/Reservoir -- And Zero leaks in the engine etc. There *might* be a small leak into the engine as I've seen some white'ish smoke come out the tail pipe on start ups.. but it is very random. 3/5 times it won't happen, then all of the sudden one start up a puff will come out. So maybe that is a bit of PS fluid leaking in, as the ACV is going bad but works 'sometimes' so sometimes it leaks and others it doesn't? --

Otherwise, all it could be is the Air control valve, there is nothing else that could lead to this problem that hasn't been replaced and from what I described..

If it is what I think it is -- Do I have to pull the whole pump out again to replace the ACV -- and say I just wanted to plug the ACV, can I do that without pulling the pump out?

I think that covers all questions I'd have --

Again, thanks. *We'll get this thing licked sooner than later*

LILEVO

iTrader: (1)

Only time I had this happen is when I was flushing my system. Either lack of fluid (fluid pressure) or air in the system contributes to you not being able to turn the wheel.

Neofate

iTrader: (1)

Fluid is fine, no leaks.. and at perfect level. So it isn't a fluid level issue. Fluid is brand new as well.

I don't think air in the system is causing this problem,.. could it be? Could the power steering virtually be non-existent at idle consistently with air in the system? Then revving it up in neutral cause it to turn like new?

With air in the system I would think it would go out, or change in intensity of how easy it is to turn while driving normally as well..

I can jack the system up and turn the wheel lock to lock a million times again, but I really don't think that is going to solve the issue.

It is amazing how hard it is to get a diagnosis on the Power Steering issues on this car. No one seems to know, not the mechanic, not the forum, not me

Given the process of elimination you'd think it would be fairly obvious by now to someone.

New rack/pinion
new pump
new fluid
clean solenoid screen
new reservoir
new HP hose
new return hose


Same ACV
Same Solenoid
Same PS Computer (I read there was a PS computer .. shrug)

Am I missing anything?

So according to lilevo an ACV gone bad doesn't fit my symptoms.. anyone else care to comment? This little problem is aggrivating because apparently alot of money has been thrown at something that hasn't 'fixed' the problem yet.. Only 3 items left and its an entirely new 2,000 PS system. I'm hoping no more money has to be spent,.. IE: Plugging the ACV (as a potential cheap solution), but I don't know exactly how the rest works (the solenoid, ACV,Computer) and what would cause this... or if there is anything else in the system I'm unaware of. These systems are a bit more complicated than most vehicles, but they aren't much more complicated than all the parts I have listed.

Neofate

iTrader: (1)

I was also thinking,.. researching other PS systems on other cars -- Most are all the same, even with ACV's.

Some people put on slightly , like half an inch smaller pulleys to increase the output at idle and low speeds. That perhaps, could be a fix in this situation? Half an inch would be enough to really speed up that pump, but utilize the same serpentine belt I would think.

Bad idea?

python

iTrader: (4)

i had the same problem, i went through 3 pumps till one worked correctly, if there is no air in the system, its a bad p/s pump.......where did u get the pump and who put it in?

19psi

could be a badly rebuilt pump if you got a remanned one...

shern

iTrader: (6)

Did you properly flush the system when replacing everything?

I plugged my Air Control Valve with an oil drain plug and brass crush washer from the parts store. Be sure to cap the vacuum supply.

You may want to pull the selenoid to ensure that it is engaging. The default valve position is normally closed. Pull the selenoid off and have somebody turn the vehicle to the on position. You should see the selenoid pull the valve in to open flow. You'll definitely hear the click.

Och

iTrader: (3)

Neo, it defenately sounds like a bad pump... or a "sticky" rack and pinion. Don't quote me on it, but I believe you can test the pump by taking off the belt, and trying to spind the pulley by hand, it should spin freely.

Nowever, consider these things before you start replacing the pump again, or buying a new rack and pinion.

Since you're saying that PS only doesn't work when the car is idle, you need to make sure your idle is where its suposed to be. If your idle is low, it could be related to the bad PS air control valve.

Make sure you've got the right type of fluid. I believe Lexus uses transmission fluid in the PS system instead of PS fluid.

Neofate

iTrader: (1)

I appreciate the advice..

Everything is right.

The rack and pinion is new -- How would it be sticky? Define sticky?

I will test the pump,.. but the old one spun freely, and I suspect this one will as well. The pump has to be working as when the car is moving is works fine.

The idle is at 600rpm when warmed up, that is dead on factory spec.

The fluid is ATF Dex IV , proper fluid.

--

Keep in mind, I didn't replace this pump.. A Master ASE mechanic did. It was the guy who sold me the car,.. he bought a reman'ed or rebuilt pump. He has been doing this for 20 some odd years , has his own shop, and told me he has specific places he like to get parts.. He had two to choose from and go the one that had a reservoir on it.

It has japanese writing on the reservoir cap, my old one didn't have that on it. Who knows.. It is black as well.

I don' think they come with a pulley, so it is my old pulley I think.

** You said you plugged your ACV with an oil drain plug and crush washer. Did this help anything related to my problem? I wont' plug it if it has nothing to do with my PS not working (very hard to turn) at idle. If it does, I will try it.

Can I somehow plug the lines temporarily to see if plugging it would work while the engine is running? Like pull the vacuum lines and put my thumbs over them and tell someone to turn the wheel?

I find it hard to believe the pump is bad,.. but maybe it is.. I really don't know,.. How can I determine that? If it spins freely, the pump is good? The other one spun freely, but it still had the same problem.

Which sort of makes me believe it is something else.

Does the Solenoid pop open with more RPM's? What would cause it to magically work with a little rev?

I've pulled the solenoid off, and cleaned it, but I didn't test it's engagement. The solenoid is supposed to open when the car is on, and close when it is off?

How exactly does it work? Just and on , off thing? Why is it there in the first place if that is all it does. Almost seems like you could take it out and loop it.

Alot of cars don't have a solenoid on the PS system.

Thanks,

Neofate

iTrader: (1)

I need this part explained as best as possible.

I've taken it off, and cleaned it, but not tested function.

Tell me how this works. When it opens, (what must occur) and why it opens. Then why does it shut? (what must occur).

Why does the system have a solenoid on the PS in the first place?

This would help me figure out some options.

Lastly,.. sounds like I can leave the solenoid on.. and just jack up the car a little on the driver side front.. have someone get in and get ready to turn the car to 'on' position. Put my ear by the solenoid. If I hear something click, it works, if I dont? Hrmm.

You are saying just to the on position put not starting the engine, right?


I do remember when I took the solenoid off to clean. I could see the metal valve type of piece that was in the rack (where the solenoid screwed into the rack) It is hard to describe.. but it was like a metal piece in there that had some odd shaped holes in it. What is that? (This isn't the solenoid I'm describing, but the hole you look into after you pull it off).

Thanks,

Sixdown

I got the ACV replaced with the pump.

My mechanic went through two aftermarket pumps that both overheated and failed before he decided to go for a new OEM one that worked perfectly. Sure it was more expensive, but it works.

Neofate

iTrader: (1)

I don't really have that luxury -- This is pretty much a done deal with this guy,.. He said he'd put on a new pump if it needed it when he sold it,.. but is wasn't in writing. I can't go back and say it isn't working right, I don't know if its the pump, but could you put another one on pretty please to see?

I'm on my own here. An aftermarket pump has to work,.. I know alot of people go through a few,.. but they do work or they wouldn't be on the market. The pump is simple in design. I could rebuild it myself,.. but it isn't a leaking problem.. so I'm not sure if it is the pump.

A Lexus new pump would be 750$ I'd imagine,.. I don't have that kind of cash to spend on a PS pump right now.. and I could very easily put that on and it do nothing for the problem.

Again I'm sincerely amazed at how no one knows what the problem is likely to be. These power steering systems all exhibit the same symptoms for every bad part?

I would think, ok, bad pump it is going to do X, Y, and Z -- If it is only doing X, look elsewhere.

If the ACV is going bad,.. it will do A, B and C.

If the Solenoid is getting stuck or not working properly, it will do E, F and G.

Process of elimination.

I find it hard to believe, I have a 'sticky' brand new rack. A bad, new PS pump (that acts just like my old pump but doesn't make any noise now),.. It doesn't add up.

It is either the ACV or the Solenoid imo. -- But I need those explained,.. I'm afraid no one really knows how the PS system truly works though. (More than just it is a hydraulic system, etc) - But what the ACV does exactly, when it engages, and what happens if it doesn't engage.. same goes for the Solenoid as I mentioned above.

bigste

Last dollar says you got air in the system. LS's are noted for being pigs to bleed. Raise front wheels, remove filler cap then sit by one one the wheels and move it end to end at least 50 times making sure the res don't run out of fluid.

Och

iTrader: (3)

Neo, I'd defenately try bleeding the system like others said. But it sounds like you've done this already.

Now, as far as the possibility of this being caused by bad ACV? Does the idle drop when you turn the steering wheel while the PS isn't working? In any case, I personally didn't remove my ACV, I looped it closed. Basically there's a thin hose (about 3/8") that goes from the nip on your intake to the bottom of the PS pump, connected to the ACV, and there's another hose that goes from the ACV to the intake manifold. I removed the end of the first cable from the nip of the intake, and the end of the second cable from the nip of the manifold, and looped them together with a connector. I then bought a piece of the same hose at an auto parts store, and ran it directly from the nip on the intake to the nip on the manifold. This completely resolved my ilde issues, and the PS is now always boosted to the max, so the steering is nice and smooth all the time. Try it, it takes literally 5 minutes or less to do, and you dont have to get dirty by removing the pump again, and the cost of new hose is 2-3 bucks.

Now, with that being said, still check your pump. Maybe it has a bad pulley bearing, which makes it hard to spin, and the belt could be slipping at idle. Have someone turn the steering wheel when the PS seems to be dead, and take a look at the pump, maybe its slipping? Also make sure your drive belt and tensioner are in a good shape.

As far as the possibility of the rack being "sticky", what I mean by that is that it could be an improperly rebuilt unit, and maybe it's piston is "sticky". Or maybe the pressure relief valve in the PS pump is bad, and reliefs too much pressure.

Neofate

iTrader: (1)

Ok, thanks for the input. Just sounds like alot of possibilities yet.

I haven't bled the system jacked up since I've gotten it back with the new PS pump.

Today driving, I would stop at a light, and put it in neutral and rev it up to see when it would 'kick in'. There is no magical number. I can rev it to 1600 sometimes and it works,, then others it takes 3300 or so. It is just like it dies at low RPM/low speed turns. No noises, no leaks.

I called the mechanic, he said he wants to try and pulling off the Solenoid to clean the filter. I told him I already did that (before the PS pump replacement) he still wants to do it 'after' the pump replacement. I am just happy he is willing to work with it for free. It is 'worse' than it has been with the new pump, that is for sure. No noise, but no PS at low speed/stop.

A woman could not drive the car, or would have an extremely slow/difficult time of it. It takes alot of muscle to turn the wheels at a dead stop without PS.

Tommorow I'll drain/bleed it for an hour or so,.. but I just have a funny feeling that isn't it.

Quite frankly I'm at a loss,.. I have no clue what is going on now. Nothing make sense, it is intermittent at best,.. so I don't know what part to point to. I do know there is no sense in putting on a 800$ "Lexus" PS pump. An aftermarket/rebuilt/reman unit will work,.. maybe the one that is on there is bad, who knows. We will exhaust other options until that is again something to replace again. At speed things work flawlessly.. but then you have to think how much of that is just how steering operates at speed (without PS, cars , to me, actually feel better without aid at higher speeds).

If anyone can think of anything to tell me to check or for the mechanic to know, let me know .. It would help.
I was thinking of printing the "PS Bible" off, but it is very sketchy and really only has how to flush , clean solenoid, and how to plug the ACV vaguely in it. I think it would cause more ambiguity than good at this point.