Gchitwood

Hello,
I am having the same PS issues with my 93 LS400. At first I was having to add fluid about once a week. Now it is worse and it has to be added two or three times a week. I do have the terrible smoking on startup. I have noticed a little leakage on the ground but not that much. has it been determined that you can indeed just seal off the control valve and not replace it without creating any issues or doing damage? If so, can someone give me detailed instructions on how to do this?

Thanks,

greg

felixtc

I have a 91 LS400 with 177K miles. I already went through the white smoke on startup headache a couple years ago and replaced the idle-up valve. If this happens again, I'd just plug it with a bolt as described in other posts on this forum. I had a power steering fluid leak that started small a few months back and I saw the high pressure line leaking and ordered a new one. The leak was slow at first, so I was lazy and just kept topping off the fluid, putting off the installation. It suddenly got much worse, then the whole pump blew and the alternator went bad. I had to get towed to a garage that quoted me $950 for the repair, even with using the line i already bought. I've now had to replace the high pressure line, power steering pump and alternator now instead of just the line. I declined the repair and paid the shop $65 for the diagnosis (I already knew exactly what was wrong) and to replace my original Lexus battery terminals, which they threw out, including the plastic covers, with new generic ones. (Didn't catch this until it was too late). I then did this repair all myself, saving about $500 in labor. I cleaned the solenoid too. I really wish I had fixed that leak when I first saw it and hadn't waited. Good luck to all. (The info on this forum has been a HUGE help)

91LS400LEX

As posted in my other topic... https://www.clublexus.com/forums/ls4...correctly.html

I have a bad PS leak. I think its the idle up valve.

It smokes on startup (heavy white smoke). It also has drips under the car. I have been told its the idle up valve, others say steering rack.

I have read were so many have changed it, but no one has seemed to have posted any detailed step-by step instructions or photos of this procedure.

I have searched and searched to find dead links, etc, but wondering if someone can please post a detailed step-by-step instructions on how to remove the idle-up valve (with the going under the car procedure and not removing the fan, radiator hoses, fan clutch, etc), as I want to put that 14x1.5 plug it and and block the lines on the intake. I have been told so many different things and so confused.

Thanks for ANY info.

BTW - my car is a 1991 LS400 (223K)

91LS400LEX

I didnt see anything about steering "shudder" in the main thread. As some of you may know, I recently plugged my idle-up valve and bypassed the vac lines, because of leaks and smoking on start-up.

However, even before this, about three weeks ago, I started getting this occasional "shudder" feel from the steering wheel on sharp turns at low speeds. I thought it was when the fluid was getting low, but it did it today after it was refilled with fluid.

Is it possible its air in the lines, or?

Thanks.

B4TM4N

iTrader: (1)

Maybe its just finally the power steering pump's time to die.. It is a 91 and 223k used, correct?

Bassil

AWESOME THREAD. Thank you so much. Now I know what to look out for on my UCF11. (A 93' LS is a Ucf11 right?)

91LS400LEX

(1991 LS400) Well, just when I thought all was well, my power steering is "acting up" again. To recap, I had blocked the idle-up valve and re-routed the vac lines, then I had a leak at the return line, replaced it and all was well. No more smoking and no more leaks! Fluid is staying full and is full now.

I was told to expect it to be harder to turn at LOW speeds, but other than that, it would not be noticable. Well, oddly, I could not even tell it at first... for several days, even at very low speeds the steering would turn very easily. I was puzzled. Then it got to where it sporadically would be harder to turn, then it would be easy again. Then it got to where even at higher speeds it was harder to turn, then easy again.

Well, today its been a pain. I drove my Mercedes most of the day, but had to go back out to the bank, so I took the Lexus. On the way, all was fine... steering was a breeze. I stopped the car, went in the bank. Came back out and started it and the wheel was quite hard to turn... even when moving and at speeds, I could tell it was not wanting to cooperate. I came home, but had to go back to town to pick up some dinner for grandpa... again, steering required a great deal of pressure to turn. Driving back, almost all the way home, the steering became very easy to turn again... even when I am completely stopped and at idle. What gives? When it was acting up and was hard to turn, it had some assist I know, because when the car turned off, its almost impossible to turn.

I am just so confused as to whats going on and getting really frustrated again.

Thanks for any info.

91LS400LEX

I have a post on this somewhere... my dad blocked mine for me. It was not that hard... and can be done from underneath. I have photos of how the hoses are supposed to run after its blocked too. The leak could be from the return line (back of the reservior)... thats where mine was leaking like crazy.... easy replacement as well.

mvbls400

This was posted on another thread so I thought it should go here....im new sorry for the double post.....
I have a 91 ls I just bought Monday and im having the same typical problem. Smoke out the tails after sitting a while and hard to steer at low speeds. If the internal leak is the ACV...what are the symptoms of the external leak. I see some tranny fluid on the engine cover on the bottom and Im worried about the alternator. Can I just pull the 2 vac lines and plug the holes and the intake/tube holes to stop the smoke? If it's not leaking from the nipples is there another place I will be losing fluid externally that I can check? Im really happy to have this new project but this seems to be the only glaring problm with the car as all the other maintenance has been done. Any help is really appreciated.

Sterling1

I didn't read the whole thread but thought I'd post what I did for the leaky ACV. I tried looping the tube but eventually it built up enought pressure to leak. I replaced the o-rings on the ACV (they had gotten very hard). I found them at a place that sold RC hobby stuff.

desertlex

Hi, I'm a new member and own a '93 LS400. Bought it 2 months ago and had to put in a new power steering pump that was leaking. I read the power steering bible and it helped me throughout the whole process. I cleaned the solenoid, flushed with Dextron III, capped the air valve nipples and the new pump came with the air valve already plugged, I had to return the first re-manufactured pump because it was not giving me any power. The second pump I installed is much better but it is still moaning when turning the weel at slow speeds or stand still. I reflushed the fluid with an aquaintance that works at the Lexus dealer and thought that would get rid of any air but it still is making noise. He mentioned the rack is leaking a bit of fluid and someday might need to be replaced. The pump is new but remanufactured. Could the pump be bad? Is there still air in the system? Does not having the air valve make that kind of difference and cause this problem?
This is becoming a big mystery and at times I think I should just live with the moans and groans which aren't very bad but annoying.

91LS400LEX

Not sure. My 1991 LS400 started suddenly smoking on startup. We did the idle-up thing and the smoke stopped... my dad put that 14mm bolt in its place and then we ran a hose from the intake tube to the front of the throttle body as instructed, but I imagine you could just use those vacuum caps to block them. I guess you could plug the vacuum lines that run from the icv valve. I would have done that, but I thought mine was also causing it to leak externally, but it wasnt. It ended up being that short return line that runs out of the back of the ps pump reservior that was leaking on mine... for years it had been leaking and I thought it was the worst, being the pump. It was not until I cleaned the mess up that I discovered it was the hose. Wish I had of known sooner, but oh well. Strange thing was not even a drop had ever got to my alternator, as it was as clean and dry as a bone. Guess it all depends on where they leak.

Anyway, I have had more problems since then... about 2 weeks after I stopped the leak and blocked the valve, I started getting a shudder on low speed turns, then occasional stiff steering... then the steering got heavy more often, at all speeds, now its pretty much the norm now. I dont know whats wrong, not getting alot of help here on it. I have cleaned the rack solenoid- it was kinda dirty, but I cleaned it completely, but it didnt help. I still have heavy steering. We tried that test where you listen for it to click when the switch is turned on, but no sound... even with a direct power from the battery, no click, so its not coming on. I thought that may be my issue, but I am being told someone on another Lexus site that this would not cause heavy steering, so now I dont know what to do.

I was told it could have air in the lines, so tomorrow I am going to get the front tires off of the ground and work the wheel lock to lock several times and see what happens.

Best wishes. The PS on these cars can be a pain in the neck! I hate them.

TexFinn

Okay... There is a whining/moaning coming from the steering when the car is warm. Doesn't do when it is cold. Fluid level is correct. I've been keeping an eye on it and it doesn't leak a bit.

So... What's there still to check? Or should I just go ahead and change the pump as a precaution?

Thanks!

sam12345

iTrader: (1)

I bought a 1992 ls400 a month ago in Vancouver Washington. When I test drove it the steering seemed to have too much free play. I live in El Paso, Tx so I drove it home (about 1800 miles) when I first got on the freeway the car was a pain because It felt like a 1970's Ford torino that had so much free play you had to constantly adjust the steering. I pulled over to get some gas and checked the fluid level on the power steering resevoir. It needed some fluid added. I figured the rack was wasted anyways so I added Lucas product for power steering. Believe it or not within 80 miles the steering felt like a new car. No freeplay. Car tracked down the road with minimum input. I haven't had to add fluid since. Moral of the story. If you rack or powersteering needs replacing anyways first try some of this stuff. Maybe it will save you a bundle. BTW I only added a fraction of the bottle even though the instructions say to add the entire bottle.

farquad

Hey, anyone got the part number to the idle control valve? i tried searching a bunch of places and i couldn't find it..
i saw this one the front page "17630-16040" but i believe that's not it