95LS400Bob

Michelin MXV4...worth the money...trust me...went through this myself recently. search for nc211 in the tire section, you'll see the thread. Blake has some Goodyears on his I believe that he likes as well. But I think the overall votes are for the Michelin's on these cars. Might be pricey upfront, but as I learned, you get what you pay for in tires. plus, with a car that is soooo sensitive to ride components, I recommend the michelin's to keep the true composure of the car's ride. Thanks for all your research to find the right tire for my car...even if it did cost you money to too do it for me. :) NC211....did you get the V rated Michelin...and was it the + tire or not? I want the EXACT same tire you did.

I've been away for a while with many other projects. But here is something I wanted to share with others that I found. My 95 Ls400 began to "digest" power steering fluid. Had no visible leaks but about once every 2 to 3 weeks the power steering would begin moaning...let me know it was low on fluild. I would add just a bit and all was well. The wife made mention of when she started the car cold...she would see blue smoke out the exhaust. It seemed to be getting worse. When I got a chance I started checking things. There are two vacuum lines that run down the power steering pump and rather disappear under the air intake and go to the pump. One of these lines connects to the intake manifold....and that line was very "squishy". Though I saw no fluid in that line I suspected that power steering fluid was somehow sucked into the intake....causing the blue smoke and the low power steering fluid. Since the power steering pump was not externally leaking, I figured I could get a power steering pump seal kit and replace the seals and probably find a bad O ring in the pump. I looked on web catalogs and found the seal kit and ordered it. When I was taking the pump off I found the valve that the vacuum lines connect to. There was no mention of this valve on any of the web pages or on line catalogs. There is a small piston in this valve that uses teflon seals..but the seals were not in the kit. I called my high price Lexus dealer (List price plus 40%) and got the part. It is called a Valve assembly 17630-16040. So if this happens to you..there is the part number you need and you can probably buy it for a whole lot less than $125 that I paid since you now have the part number. It's been a week...no smoke and so far so good. Just a heads up if you have this type of problem.

Sorry I have not been here on line very much. When I did mine...I did not remove any crossmember. I just jacked up the motor and got the new mounts in there. It is crowded but I got them in there.

There was no "drama" in my post. I simply explained what made me even try a Lexus in the first place and some differences between cars I had owned. Wasn't a Lexus commercial nor was it bashing other makes of vehicles. PS: When the vehicle you drive everyday has to go out and fix those vehicles that are out there broken down on the highway you need dependability. When you have owned 4 of these over the years and they ask for little more than tires and brakes...you tend to get impressed with the company. That's not a Toyota commercial. That is fact.

Take them off and drive around the block. Or look through them. Everything else is just guess work. Bought an Audi once. Bought the car for $100. Because you could rev the engine in the driveway all you wanted and it sounded fine. But try to drive it and it would not go over 25 mph. Got it home (barely) pulled the cat. The stuff had broken up and formed a perfectly round ball. Soon as you would move the car forward...the ball plugged the exhaust outlet. Be sure to check the dumb stuff first..like fuel fliter and that sort of thing.

I always liked a nice quiet road car. Relaxing road trip. I had Cadillacs and Lincolns for that reason. Seemed every now and then I would have someone in the car with me that would say "You think this is nice...try a Lexus." After being told that by a few different people...I decided one day I would get one. That is...when they came down in value (depreciation) to what i was willing to pay. The other reason was I had owned several Toyota pickups...and I just could not believe how good they were. Reliable and strong. I bought a 95 Ls400 and I seldom drive it. The wife drives it everyday. But the quiet, the ride and comfort far surpasses anything I ever had. Each time I drive it I am still impressed. And now I know why those people said "Drive a Lexus". I am a mechanic, engine builder, etc. I appreciate the quality probably far more than many people do. The Lexus does everything quite well. A far cry from all the cads and lincolns I owned. The cads were soft and mushy...leaning going around corners. The Lexus flat in the corners. No diving here. I thought they were quiet. I thought a Lincoln was a little quieter but not as smooth. Then the Lexus. At a stop light...you wonder if it is still running. A loud motorcycle goes by and you barely hear it. The doors close like a vault. I've had my car at 145mph....and the wifey asleep in the passenger seat never knew. LOL...even when she woke up...and saw the speedo. But she didn't know by noise and vibration. Hard to describe...just an appreciation for something made well.....and better than most.

Remove each converter and look through it with a light at the other end. See if you can see through all the honeycomb type stuff and be sure none of it has broken loose and is rattling around inside the cat. In the US it is against fed law to tamper with a cat converter. But you said you are in another country. I would also think you will get a check engine light if you gut the cats on a 1995 and up..because there are 02 sensors that read exhaust after the cat. Not sure on earlier models.

If you watch the tach carefully and catch it...you'll find that yes...the idle goes way low...and then any load (such as turning he steering wheel) and the motor dies. This says to me the idle air control is closed or near closed. The question is "What closed that idle control valve and why?" The IAC is a pulse motor. It has to be pulsed a lot of time by the ECU to near close position. I had my IAC apart and tried to duplicate the closing on the bench. You would not believe how many pulses it took to get the motor to close the valve even one turn. We don't know how the ecu is programmed. But for some reason that IAC gets closed. Only way a guy could prove this (IAC is closed) would be to let the car do it's thing and die. Then without even touching the key..get out and remove the IAC and look at it's position. I suspect it would be closed as the ECU commanded it to do so (for whatever reason). Then when the key is cycled...the ECU resests the IAC back open...and all is normal again. Only to repeat down the road. If mine died in town I would catch it. But it always dies in some lonely town in the dark when all you want to do is get where you are going. I even came up with a throttle control solenoid I rigged up...I could turn that solenoid on and hold the throttle open just a tad to keep the engine running till I coudl get somewhere to pull that IAC off and check it's position. But the car never died. Figures. LOL> I'll catch it someday.

Here's the latest. When I changed the ECU to the 49 state dealio...we drove the car over the exact same ground where it died and it was fine. Thought we got it. Then we made a trip to Phoenix and low and behold...she dies. Only now..for some reason...instead of dying after 60 mile jaunts...you have to go about 100 miles. Strange indeed. A few months ago we went to California...a 150 mile trip one way. Never died. Same deal on the way home. Never died. Since the car runs flawless in every other way I just never got around to doing the $99 rebuild on the ECU. What I would like to have is the new ECU...the one I feel Lexus did to solve the problem. That is the 89661-50224. But I don't want to pay $1000 for it. Since this is the wifes around town car anyway we are living with it. Someday I might find the new ECU in a wrecking yard with some luck. So I think I still have the "dies after the highway cruise problem." Gas prices what they were we didn't do any long highway drives. Once in a while..I get the check engine light. About once a year. And that always turns out to be the P0 420 code. I simply read the code with my diagnostic tool and erase it. The car passes all smog checks and reads 000 on all smog checks. I've looked at both cats and they are clear. Not going to throw money at as many others have chased this P0 code and replaced 02's and cats and still get the code from time to time. So we drive her on. It's the "why" that always puzzles me.

The ECU and dying problem was more related to the 95 and 96's from all the research I did. And that was after a highway cruise....otherwise it never happened. As I remember, the IAC is different on the 94's than the 95 and up. The IAC would be the first place I looked with the problem on your car. Not saying it is not a ECU issue..but I would go for the IAC first. We know the engine computer controls the idle function through the IAC. Opens that valve to let more air in to speed up the idle depending on load. First thing to watch for is cold start and warm up rpm. If the engine goes to high rpm and then tapers down in rpm as it warms up...then the IAC is working. Should also be a difference when turning on the a/c. If it is doing all that normal, I think I would look at the connections at the IAC and also remove it and make sure everything is clean. A new IAC is a $510.94 item...so it would be nice to find a used one for sure if it is suspect. 1993 and 94 Ls400, SC400 use the same IAC. A new ECU would cost close to $1000. Again 1994 is different. And I show 1994 ecu is by itself as far as part number. Searching a used parts site, the numbers I come up with for an ECU for 1994 Ls400 is: 89661-50142 if it is a 49 state car. 89661-50151 if it is a Cali car. ECU from a 93 might work and probably would but a 95 up will not for sure. 93 ecu numbers are 89661-50141, 89661-50140 for 49 state. I don't find any different numbers for Cali cars in 93. Hope this helps a little. These intermittent problems can be a bugger to find.

Please keep us posted on this. My throttle body and IAC were clean and I could not catch the IAC malfunctioning. Also...that ECU that you list 89661-50233. I don't seem to find that part number anywhere. I do show the latest 95 ECU was 89661-50234. California ECU.

If your car dies or low idle and does not require a "highway cruise" to do this, then I would definately look other places first. The car dying or low idle around town would sound like another issue. First place I would look would be the idle air control valve. Perhaps it is sticking or bad. Throttle body could cause these problems also. The idle air control valve is an air control valve that contains a pulse motor. The ECU pulses that motor to open the valve to regulate idle speed. Any change in engine load is sensed by the ECU and the ECU pulses the IAC to open or close slightly to allow more or less air to the engine to maintain the proper idle speed. But the engine dying after a highway cruise but acting totally normal otherwise has been found to be an ECU issue. I have no way of knowing the programming Lexus is doing to the ECU but it is my bet that after "X" amount of rpm in high gear...the ECU commands the IAC valve to close. Maybe Lexus does this for better signal through the MAF sensor...or maybe they just program it to close (or nearly close) since idle is not needed. But for some reason it fails to open when we return to idle after the highway cruise. If we restart the car....all is normal again..for the ecu resets and we idle normal again till the next cruise. That's the ecu issue and doesn't sound like you have that.

It's an ECU problem. Throttle bodys that are dirty don't wait for 30 min or more of highway driving before showing a problem....nor do they fix themselves as soon as the car restarts. Probably the best question is the "why" the ECU starts doing this. It certainly didn't do it when it was new. It has to be an aging process...maybe something to do with the circuit board itself...from the many hot and cold cycles it has done over it's lifetime. And this could very well be why many of these same cars get the "P0" check engine lights after a cruise.

I haven't had any check engine lights and no problems whatsoever. BUT..I have not driven the freeway for any length of time...which is when I would get a P0 code. After watching guys checking, swapping and replacing the 02's front and rear...and even replacing the cats and still getting the code....my thoughts are that this is and ECU glitch. Since when the code is set there is no change in engine tune...I believe I will just ignore mine if it comes on again. And get out the electrical tape to cover the light. And surely the code will appear again if I take a long highway cruise. And mine just got through the smog test with flying colors....like it always does.

Yeah get rid of the code it should pass with no prob my 1990 did something like that. But now I think I'am having the ECU problem my 1990 LS400 will not idle at all it did have a high idle about two months ago then it started to get lower and lower until the idle was at about 100 to 200 rpm, what do you think? ← That sounds like idle air control valve problem to me. Does it have fast idle when started up cold?