IS400

Wooo hooo! Good for you! Mine solved my soft braking problem that was there before and after each brake job no matter what I replaced.

By the way...what's the best way to do that? Take cap off overflow tank and squeeze the hoses?

I agree with Muskmelon. I 'burped' mine after a timing belt repair by taking off the access cover by the thermostat and ran the car while adding more coolant until she could take no more. It is messy, but I had no heat like yours until I got the air out of the top of the engine. It took about ten minutes of back and forth on full blower and heat while waiting for the theromostat to open up and accept coolant properly.

There has to be an easier way but that is what I did and it worked under cold outside DIY conditions.

Hate to pepper you with questions but by the access cover do you mean the cover with two bolts that hold the thermo in or something else?

Yes that is the cover I used.

These are first generation IS300 wheels. Nothing better than the stock emblems to make the car guys scratch their heads! :D

The purpose behind sealing a sub woofer is to make sure you get sub-harmonics in the first place. The sound is actually coming from the surface of the speaker and not from inside the trunk. You will get much poorer performance if you vent the trunk. My guess is that you have a torn sub-woofer diaphragm or have loose hardware. The torsion bars (look like coat hangers) that hold the trunk up could also be at fault.

The pressure wave you are talking about does not rattle anything, the movement of the sub as it cycles back and forth is what is shaking your trunk parts.

If you trust your buddy, have him lock you in the trunk and see what is rattling! LOL, no don't do that. Just kidding!

Good luck! :D

By the way...what's the best way to do that? Take cap off overflow tank and squeeze the hoses?

I agree with Muskmelon. I 'burped' mine after a timing belt repair by taking off the access cover by the thermostat and ran the car while adding more coolant until she could take no more. It is messy, but I had no heat like yours until I got the air out of the top of the engine. It took about ten minutes of back and forth on full blower and heat while waiting for the theromostat to open up and accept coolant properly.

There has to be an easier way but that is what I did and it worked under cold outside DIY conditions.

I agree with Alexander. After doing mine I got a much firmer brake feel too.

Case in point, after the trunk wire repair I nailed the brakes to avoid an accident and the ABS activated (dry pavement.)

Problem is that my mom was in the passenger seat and she was not buckled in! Kind of funny and tragic seeing her whole body jammed into the footwell.

She does not forget her seatbelt anymore! Before the repair I could not upset a cup of coffee with full braking. :P

I have a 1994 LS400 that the battery will drain to 4.5v overnight. I put in a new battery and it was dead the next day. I drove the car all this past week but I would disconnect the positive cable every time I parked the car for more than 30 minutes. I would connect it first thing in the morning and disconnect it when I got to work then connect it back up when I went home after work and then disconnected it after I got home and left it off overnight then started the same procedure the next day. I drove it all week without a problem. When the car is running the voltage at the battery is 14.4v which tells me that the alternator is ok. I hooked up an ammeter to the positive terminal and then to each of the positive leads (individually) and there was only .001 or 1 milliamp of current on the lead going to the alternator and nothing on the lead going to the starter. I thought there would be a large current draw since my battery would lose 8v in 12 hours. I have disconnected the trunk bulb, power to the CD changer, and power antenna but still the battery will drain overnight if positive leads are left connected to the battery. Any ideas what would drain the battery overnight that would not obviously be seen or heard.

CLowe

You need to put the meter on the positive lead and ground it to the engine and see what kind of amp draw you have when the car is off. I'd say you are doing harm to your new battery cycling it like this.

You can also start jumping across fuses with your meter to check what is actually drawing power also. My guess is a pretty big short somewhere. Most components fail electrically 'open' but you probably have a closed circuit somewhere as you have already guessed.

If you can isolate the general area of the problem you are going to save loads. I had a boyfriend with a C5 corvette and he paid thousands for GM to NOT find the electrical problem and ended up ditching the car until his neighbor told him about some obscure factory defect with the starter circuit, which was a dealer paid fix and solved the problem. The dealer would not give him his money back for the hours and hours of diagnostic bills though...

Good luck!

I was wondering if there are any diagrams on how to remove the door panel. The handle on the door just broke and will not open from the inside, having to roll the window down to open the door is going to get old fast. If anyone has an suggestions it will be helpful.

Do a search on this site for door panel or speaker replacement and you will find links to some great tutorials.

I'd do an exhaustive search on this board for 'power steering.'

These cars are notorious for P.S. problems.

Check the reservoir regularly and add fluid as needed until you fix the problem.

Make sure to watch the alternator because it will leak fluid all over the wiring since the pump sits above it. Good luck!

Question: I purchased a 90 LS400 in August--it got down to 30 degrees last night, the first night it's really been cold since I've owned it. This morning when I started the car, I got a loud, strange whine from somewhere under the hood. Not sure where exactly it was coming from. When the car engine got warm, the whine stopped. Is this something I should be concerned about? ANy kind of new, strange noises kind of freaks me out. This is my first Lexus. Any help would ease a troubled mind.

Get a small lenth of pvc pipe about 2-3 feet long (1" dia is more than enough) and use it as a way to isolate where the whine is coming from. Take off the air cleaner snorkle (big wide plastic piece over radiator) first. Let car cold soak as you mentioned and start up and check all the pulleys and devices you see near where the noise is coming from. You are using the pipe as a way to hear what is going on in a certain area and isolate the rest of the noise. Hold it close to your ear and cover around it with your hands to make a better seal.

My guess is a bearing going bad on one of those pulleys. Remember your alternator is way low on the front passenger side so don't forget to check that one too. You will not be able to access it from underneath unless the splash guard has already been removed.

Mine ended up being the idler pulley in the middle. Sprayed it with that belt squeal stuff and the sound went away for a few seconds. You can try the same if you are CAREFUL! Good to peace of mind if you can find what it is and plan for the repair.

Question: I purchased a 90 LS400 in August--it got down to 30 degrees last night, the first night it's really been cold since I've owned it. This morning when I started the car, I got a loud, strange whine from somewhere under the hood. Not sure where exactly it was coming from. When the car engine got warm, the whine stopped. Is this something I should be concerned about? ANy kind of new, strange noises kind of freaks me out. This is my first Lexus. Any help would ease a troubled mind.

I would hire a lawyer honestly...

Me too; a '00 model with less than 90,000 miles is worth too much ($10k-$12k according to KBB private party) to just let the insurance company off the hook.

You do not need a lawyer. The state insurance commission is the only call you need to make. If you indeed were paid up and nothing else is amiss you will not have a problem. Heck the local newspaper could make a story of this if your facts are accurate.

By the way, where is there snow already? Those pics have me asking a lot of questions now.

One thing to remember about snow tires is that they have a much softer compound and will wear out fast in warm weather on dry roads. Put them on when it stays below freezing at night and take them off when it gets above freezing every night, at the very least.

I have a house in Maine and from Nov 15th to March 15th is snow tire weather. Some years you can get lucky and go a month more without snow but it all depends on how many Vermont mountains are near you. Inclines are a REAL !Removed! in this car without snow tires!

Also remember the narrower (without going crazy of course) the better with snow tires. It allows the weight of the car to cut though and get to the pavement rather than snowshoe and sit on top. Good luck and slow WAY down until you get used to the slip and slide of New England winters! ;)

Check the rear sub woofer speaker and see if it is torn or damaged. Most 400's have this problem eventually due to the location of the speaker/sub sitting in the roasting hot sun under the rear window. Just a guess, but good luck finding the issue.

I drive exactly the same kind of cars as you! LS400, a hi reving special sport edition miata and an izuzu 220 hp suv! We girls think alike! Oops I mean you think like me! The car gets lower gas mileage with regular. I'm sure the computer will let it run on 104 octane too and get better gas mileage since it is a higher energy fuel, so what is your argument again? You did say the computer adjusts to prevent predetonation right? So where is the damage? I can understand if you are used to twisting the distributor too much on your old mustang, but nah it just is not the same on these cars... don't buy it yet.

BTW do you know the compression ratio of the UFZ 4.0 Liter in the 400's at each model year? Here is where we can break down how high performance this engine really is. Remember it VARIES for certain years and the discussion loses a lot of traction if you are talking about certain years. Traction... ooooo....car pun, sorry. :D

"The octane rating of a spark ignition engine fuel is the detonation resistance (anti-knock rating) compared to a mixture of iso-octane (2,2,4-trimethylpentane, an isomer of octane) and n-heptane. By definition, iso-octane is assigned an octane rating of 100 and heptane is assigned an octane rating of zero. An 87-octane gasoline, for example, possesses the same anti-knock rating of a mixture of 87% (by volume) iso-octane and 13% (by volume) n-heptane. This does not mean, however, that the gasoline actually contains these hydrocarbons in these proportions. It simply means that it has the same detonation resistance as the described mixture.

Octane rating does not relate to the energy content of the fuel (see heating value). It is only a measure of the fuel's tendency to burn rather than explode."

Octane has nothing to do with energy. The reason you get less fuel economy with a lower than called for octane is that your computer has to slow down your timing to avoid predetonation, causing it to operate less efficiently. In most cases with modern cars, they can run fine on regular grade fuel, albeit with less fuel economy and a decrease in horsepower at WOT. If you decide to do this, you should watch specifically for pinging, since if you experience prolonged predetonation, you will damage your engine. My owners manual states with regard to fuel that 91 should be used for optimum engine performance. It further states that if premium is not available, that 87 may be used temporarily.

Using your argument on octane and energy, an engine designed to run on "regular" would have improved fuel efficiency when running "premium". I have never seen anything to support this theory.

Uh huh. ...still waiting for the compression ratios; as they changed for each year of the 400's, so we can seperate apples from oranges... ...btw you might want to go on the new generation mustang forum and see if those boys notice a mileage or power increase from running premium. Tell them about your Honda S2000 too.... ....it will let them know you are a real car guru. Keep me posted!

It's not uncommon for the water pump in these Lexus's to go bad around 100-150,000 miles...Infact alot of people just change them out when they change the timing belts....Easy access when changing the timing belts... I have changed both out a few times, it's not a big deal once you remove all the plastic crap that surrounds the motor...

why should you change water pump .. with the change of timeing belt .. while the water pump is not gone bad ? seem like u guys got alot of money .. lol .. if it was me then i would wait until its gone bad !!

LS pumps are designed to last app 120k. So do the math. If the TB is scheduled for 90k, that means the next change out is at 180k. The math says your pump will fail before the next scheduled TB service. This is why as both IS400 and JIBBY mention, the pump should be replaced along with the pulleys and tensioner at every TB service. Read up on what's involved with the service to see why you don't want to go in there more than you need to:

http://www.lexls.com/tutorials/engine/timingbelt.html

and an excellent write up by IS400 herself:

http://us.lexusownersclub.com/forums/index...showtopic=49817

Thanks for the shout out! I am going to write one on my cold start valve replacement too as soon as I get all the info and garage time lined up.

What they have to gain by recommending premium is a higher fuel economy rating. These engines/cars were introduced during the OTHER recession, 1990-93. The 4.0 is fuel hungry enough, let alone having sales affected by publishing the fuel economy of it running on a recommendation of 87 octane. Yes it is a luxury car, I know, I know.... Have you ever seen how cheap the old people are in the wealthy communities in Florida and Arizona? My family has a winter house in Boca Raton. They DO care for sure.

I think your logic is reversed on octane and fuel economy. A high performance engine that runs at higher than typical compression requires the use of higher octane fuel to avoid predetonation (i.e., pinging). It has absolutely nothing to do with fuel economy. That being said, if pinging IS detected, the car's emissions system will trigger an adjustment in timing in an attempt to avoid the pinging, but in so doing, the engine will be less efficient.

If your car is designed to run on "regular", there is no benefit to using "mid-grade" or "premium". If your car is designed to run on "premium" and a lesser grade is used, the risk is pinging, or at a minimum, lower efficiency and therefore fuel economy as it adjusts its timing to avoid the pinging.

Given that prolonged predetonation can cause serious damage to an engine, why risk it?

I drive exactly the same kind of cars as you! LS400, a hi reving special sport edition miata and an izuzu 220 hp suv! We girls think alike! Oops I mean you think like me! The car gets lower gas mileage with regular. I'm sure the computer will let it run on 104 octane too and get better gas mileage since it is a higher energy fuel, so what is your argument again? You did say the computer adjusts to prevent predetonation right? So where is the damage? I can understand if you are used to twisting the distributor too much on your old mustang, but nah it just is not the same on these cars... don't buy it yet.

BTW do you know the compression ratio of the UFZ 4.0 Liter in the 400's at each model year? Here is where we can break down how high performance this engine really is. Remember it VARIES for certain years and the discussion loses a lot of traction if you are talking about certain years. Traction... ooooo....car pun, sorry. :D

I concur with the majority that replacing the timing belt is good preventive maintenance. Sure, the belt may make it to 150,000 miles or more.............but what if it doesn't? You don't get a warning light before the belt goes and significant engine damage occurs.

On the issue with the grade of gasoline used, I would be much more concerned about pre-detonation (pinging) than trying to compare fuel economy on different grades. Premium fuel is required by engines that run at higher compressions to avoid pre-detonation. Pinging over time will damage your engine internals.

I have never experimented using lower grade fuel in my Lexus......so maybe you can get away with it without pinging. My thought is with such a small difference in price, why risk it? Lexus does not have anything to gain based on what grade of gas that you use, so why not follow their recommendation?

What they have to gain by recommending premium is a higher fuel economy rating. These engines/cars were introduced during the OTHER recession, 1990-93. The 4.0 is fuel hungry enough, let alone having sales affected by publishing the fuel economy of it running on a recommendation of 87 octane. Yes it is a luxury car, I know, I know.... Have you ever seen how cheap the old people are in the wealthy communities in Florida and Arizona? My family has a winter house in Boca Raton. They DO care for sure.

I think they did that deliberately just to annoy people. Like there was not another place to put it for easy access.

The starter on the LS400 sits in the middle of the engine beneath the intake plenum, so the top portion of the engine has to be remove in order to replace the starter, hence the high cost.

N.E.O

Don't know, but with all that space there why not? Actually, other manufacturers did the same too; overhead cam clear out a lot of space between the two cylinder banks.

N.C.O.

The fact that the car is so quiet on start up is because of the location of the starter. You ever stand next to a mustang 5.0 when it is starting? Sounds like a worn out hairdryer! I agree with the large amount of space in there. Remember than a lot of piston engine fighter planes in WWII stuck a machine gun or cannon in that space! (ME-109, and IL-something or other Sturmavik)

Unfortunately my beautifull 1995 LS400 Mk III failed it's MOT (annual UK mechanical test) with "excessive play in inner rear bushes" on the rear wishbones (I think you call them 'control arms here in the US), on both sides.

The tester mechanic showed me, yes you can feel play in the wheel and see the rear most wishbone mounting moving when the wheel is wiggled.

Has any one replaced these bushes, I am using some ADUS 578 bushes (or bushings as they are reffered to in the USA) purchased from LDP Autoparts on ebay.com as reccomded by some US owners.

The problem seems to be that the top hats are too big and the wishbone unit is now too long to fit back into the subframe mountings.

A picture will follow tomorrow, so you can see my dylema.

Search this site for tutorials and you should fine a link to a website with the repair. I used it to do mine. The installed with a lot of elbow grease but the new parts seemed to be the right size. I hope you got the right parts!

This is interesting. I just bought an LS430 2002 model with 150,000 on the clock. It loses a little coolant when the pressure is greatest, ie. if the tank is full or revs are high (I keep both low now and don't seem to lose any).

There is also a noise from the area of the water pump so I'm inclined to go with the "replace the water pump when you do the timing-belt" theory.

Only thing is that the belt was done at 125,000 miles so I'll be keeping a weather eye on the pump/coolant for the next 100k.

Still that's only 18 months for me so I'm definitely going for the "pump with the belt" scenario and it'll soon come around.

btw at a previous owner's Lexus service the "noise from water pump area" was reported and the consequent action was to replace the v-belt. Low coolant was also mentioned twice on service reports but the action was simply to replace the coolant. All this has really encouraged me to do most work myself. (not the belt though - or the suspension bushing, which I plan to get done around 250k)

Thanks for all the info. - great site!

Regards,

Mike

Mike it looks like your belt was changed without doing the water pump. It makes me suspicious of the rest of the repair. I have done both myself and cannot imagine any logical person or responsible shop that would do the timing belt without the water pump along with it. I'm sorry for your predicament!

that is probably the ugliest thing ive seen since i went to a bar and got really really drunk and woke up next to sasquatch

You are being pretty mean. It takes balls to post pics on here with something new. I dare you to post a pic of your face and see what the rest of us here think. C'mon give the guy a break, he is being brave IMO :)

I'm not trying to scare you. When the valve is disconnected, the residual pressure will be released, unless it has bled down. Wear eye protection. My point was that diagnosing such things is tougher than replacing them - a "cart before the horse" situation. Which is why I wonder how you have diagnosed this problem. Maybe you're right. Maybe not. I just don't like replacing parts - I like to know that the part WILL fix the problem.

Point taken. Thanks for the heads up on the line pressure and need for eye protection.

"In my car, I decided to get clear tailights since I already had the from bumper lights clear. I bought them off e-bay and here's the link if you decide to go for the clear look instead of the smoked.

http://cgi.ebay.com/ebaymotors/LEXUS-LS400...sspagenameZWDVW"

Please upload a pic of your car with clear tails or mabe a link to one that has a pic of a completed installation. I would like to see how big the change is going to be before buying. Thanks for the link!

So you're sure it's the valve, but you're not sure what happens when you disconnect it?

Ahem. Lets see... ...I did ask about the location and any issues with its installation did I not? SRK, are you just trying to scare me? Sounds like it.

Thanks eatingupblacktop! I like all your posts. You are very constructive in your comments. VERY cool!

Hey killerfatty, I will post my results as soon as I investigate the repair and get the info I was looking for.