yotoy82

Well some of you may have seen a few of my posts on here, My family has 3 LS400's (95-97 generation), and I have learned a lot thanks to this forum, and from some of my own trouble shooting, and I thought I would share my experiences with everyone here. Pictured below is my 1996 LS400 with 216,000 miles on it. 1. STRUT RODS.... All 3 of our LS400's regardless of mileage have had the strut rod problem. Some worse than others, but its totally something every LS400 should have changed at this point, either due to age or miles. Its also a very very hard thing to pinpoint and most dealers and technicians won't notice it or tell you that its a problem. But when you go over any cracks or humps, it will feel it. The rod itself is fine but the rubber bushings can develop small cracks and apparently this is enough to let it wobble around. Also the bolt holding it in seizes up and is hard to remove. My suggestion... buy two new strut rods with the bushings already pressed in, they are different parts for the left and right, and have them replaced. Go ahead and order the bolts and nuts for them in case your mechanic has to cut the old ones out! This will make a big difference, trust me. Around $200~ ish from Lexus Sewell for forum members, and $200 for labor to change them out, don't quite remember if it would need an alignment or not and if thats part of the $200 or not. 2. Lower Ball Joints... WIth a car this heavy, if it has never been changed, go ahead and change them out while you are getting the strut rods changed, these arent expensive parts. 3. Engine Mounts/Transmission Mount replacement: This by far was the BEST thing I ever did for my LS400. They were disintegrated basically. It made a HUGE night and day difference in the car... I would say like 80% quieter, the idle smoothed out, drove so much better, shifted FLAWLESSLY! I suggest EVERYONE has it done if they haven't. These are special mounts, contribute significantly to the smoothness of the car and they are the reason why you can balance a dime on the engine or a stack of wine glasses. They get old over time. 4. Shocks/Struts: My LS400 was kinda boatish like on turns and in the wind. I replaced all 4 shocks, bumpers, strut mounts, and the sway bar bushings. Comfort wise it wasn't a huge difference and not sure if it was really worth the expensive labor and parts, and I would say that the original shocks could probably go easily 250,000 miles but if you have the money to spend it does make the car feel tighter, and brake a lot easier. 5. Tire Balancing: This is important. Get the ROAD FORCE balancing. It is done by a HUNTER brand machine. It makes a world of a difference with the LS400. I guess the LS400 is very sensitive, and this special balancing helps a lot, you really can tell a difference at highway speeds. 6. Timing Belt Service if hasn't been done is important, since you will be paying for all the effort to get to it, make sure you change the water pump, all the seals down there, idlers/tensioners/pulleys whatever, the drive belt as well. Thermostat, coolant, distributor caps and rotors as well. Spark plugs every 90,000 miles, transmission fluids, cleaning the transmission filter, new air filter, new coolant. 7. Cabin Filter: Many people neglect to change this. Some have NEVER changed it. Its very easy to get to, just open your glove box, it should be back there, pull it out. It is probably black and covered in insects. Cheap easy DIY. 8. TIRE PRESSURE: 29 PSI is what Lexus recommends for the OPTIMUM comfort of your car. Forget about anyone who tells you that higher tire pressures mean better tire life and mileage. You will not get better mileage.. use what the company tells you! 9. Oil changes: If you aren't a taxi driver or towing other things behind it, 5000 miles oil change intervals are good enough. 5w30 = smoother quieter ride with best mileage. Use the original toyota filters, they arent expensive especially if you buy a box of 10 from Sewell. 10. PCV Valve: easy change, make sure you order a new grommet to insert it in and be SUPER careful removing the old one, as it has hardened by now and might fall into the engine. 11. Coolant Temp Sensor: mine was cracked in two pieces, Id say change it. 12. Fuel Filter after this many years/miles will probably be dirty, I suggest changing it when get a chance, its not going to hurt. 13. One of our LS400's had the UV blocking tints applied to the windows and the leather is still SOFT and Supple! But the others have started to crack a bit, I guess from UV damage. Keep the leather oiled and conditioned often. 14. Wash often, wax when needed. Use Rain-X on the windows/windshield. The best wipers I have found were BOSCH EVOLUTION all seasons. Quiet, easy to install, streak free, and affordable (amazon) 15. Radiator Cap: put a new one on, didn't need it but couldnt hurt. BTW, I always try to use Lexus/Toyota parts only. This was at one point the best car in the world, and possibly still is. Parts can be duplicated but they won't be the same.... parts on a Lexus look simple like other car parts, but they are really very different, using different types of materials. They all combine to give the quality smooth ride and quality/longitivity. 16. The previous owner changed the antenna mast, the hood shocks, the power steering pump. I had to replace a broken door lock actuator. The lights/readout on the cassette/radio are broken on the two LS400s with the stock lexus system, but the one with the Nakamichi system is still fine. Id say all of them have worn out uv damaged rear subwoofers though. Depends on how important audio is for you to change. 17. Fading area of paint above the rear bumper remains a problem, as is rust seems to want to develop around the body panels above the rear wheels. I tried painting my rear bumper my self as you can see below, it should be the same color as the car, but came out a funny grey plastically color, will have it professionally done when I can afford it. 18. Original mudguards: not really available unless you want to spend $400 bucks for the originals. I bought some generics online and had them screwed in at my body shop, very cheap parts very cheap installation, really helps keep the paint clean and away from rock chips. 19: Rock Chips: buy paint sticks online and touch up all chips and paint scratches right away before they develop into bigger problems! 20: Silicon Lubricant: spray onto all rubber and weather stripping each year. I heard this helps keep them soft and prevents them from drying out. 21. I have Michelin MX4 tires but they are not so good in the rain, look forward to replies on which tires to get whenever the time comes (they have tons of tread left) 22. Battery: The LS400 has a pretty standard battery, but it is covered with an INSULATOR. If you get the battery changed at cheapo places, ie autozone/oreilly, sometimes they remove the insulator cover when taking the old battery out. This is a problem because it is hard to find and helps keep the battery protected from the engine heat, in effect helping it last longer, so keep an eye on that! Any corroded battery terminals should be changed! 23. The drivers side door handle tends to crack, especially from rough winters, be careful about this. In general, Id say my LS400 rides better than most new cars, I average about 22-23 combined city and highway in the summer. I take care of any odd sound when I hear it, wash it regularly. Drives tight, you would never believe it has 216,000 miles on it. An exhaust guy told me the EGR pipe has a slight crack in it but I'm not going to pay anyone the huge amount the book says to replace it, ie dropping the transmission. Will have to find someone willing to remove the catalytic converter and using some extensions to get to it! But no hurry as its still dead on quiet after the engine mounts were changed! If you got spare time, you can buy those LED/SMD lights and change all of those geeky old orange lights in your car. There are tons, dome light, glove box, trunk, reading lights, courtesy door lights, parking lights. Headlights aren't so bright, have had them adjusted a bit and it made a world of a difference, seemed VERY low to the ground. I guess my next upgrade would be the HID/Xenon if anyone can suggest a good brand. Or possibly will get the new style depo lights, they look a lot better. Take care of this car and it will continue to take care of you. The ONLY break down I had was once the fuel pump went out on me. The car is kinda boring to drive and leaves you wanting more, but its a solid transporter.

When you switched in the "other" sensor was the battery disconnected long enough that the ECU had to "relearn" all of the sensor operating parameters, ALL sensors. And it will take up to 200 miles of "mixed" driving to relearn. At idle or simple cruise it is the upstream oxygen sensors that are used to control, SOLELY used, the A/F mixture. Only under "power" production mode is the A/F mixture control switched over to the MAF/IAT module. AC is OFF always in the winter, I don't have a problem with heating. About 10-12 minutes the heat is coming out nicely and the car warms up just fine on the inside, plenty of hot air blows. I've disconnected the battery for hours over night. I'm not as concerned so much but it doesn't seem right. The car doesn't drive or sound as good until its COMPLETELY warm, and that little 1/4 of an inch higher that it eventually gets to close to little less than halfway is when the car seems to settle down, get smooth, quiet, fast throttle response, and that "lexus feel and power". But soon as I turn the car off again, even if its 40 degrees, in like 20 minutes the car is back to COMPLETELY cold and I have to start the whole slow process of warming the car up. This car just does NOT want to get warm! :-( People have overheating problems, I have the opposite lol.

Ok, I'm just curious.. My 1996 LS400 takes literally 14 minutes from a completely cold morning (30F) from starting the car to the completely full normal operating temperature. It takes 6 minutes for the needle to even move. I even had the thermostat changed and its still taking that long. But my fathers 1995 LS400 gets to full operating temperature in 6-8 minutes. How long does everyone elses LS400 take to warm up from completely cold engine to normal operating temperature?

Car-Part.com Has a listing of almost every part in every junk yard in usa. Lexus-sewell for new parts is my favorite, they give special discounts to those who use this website, their catalog is easy to browse, and they ship fast. I have yet to find anyone who can beat their prices.

I was switching out the old orange drabby bulbs to the LED ones, feels so much more fresh, and that button was just right there below it im like hmmm. Oh well, no launch sequence was activated as far as I can tell!

Ya I pushed it once and the remote control unlock didnt work.. Pushed it a second time and the remote would work but the car would not make a beeping sound, and pushed it again and remote works and makes the beeping sound when locking/unlocking!

Its pretty easy actually. Just remove the top timing belt covers to expose the camshaft belt pulleys. Then get a socket and ratchet (or maybe a bar)and turn engine to TDC. The cams should align exactly to some marks on them and on the cover behind them. If they don't turn crankshaft ome more full turn clockwise and recheck. It should be obvious if the belt is misaligned. A tooth offset would be about 1/4" error on the marking points. Ill be having a mechanic at the dealer do it for me. I know the timing belt service is quite expensive. So it shouldn't cost a lot to just have them remove the cover and have a look?

I just noticed this button today when I was changing a light bulb down there. I circled it. Does anyone know what it's for and what it does. http://img692.imageshack.us/img692/9648/img1715rm.jpg

I did a 3 step fuel system cleaning... One bottle in the gas tank, throttle body cleaning, and some kinda chemical they ran through the engine with a vacume pipe for a while. I dont think it would be too easy to literally take the fuel injectors out of the car.

I put a new thermostat in shortly after buying the car, the old one wasn't in great condition, and the new one helped a lot. But it could have been a dud, but even when the car gets warm, the mileage stays the same around the city even in the heat of the summer. I think I will go ahead and do the ECU Engine Temp Sensor, do you know the part number for a 1996 LS400 and where it is on the engine (tutorial anywhere) I already changed the engine coolant temperature sensor, is this the same one you are talking about? From your description, I wonder if the T-belt is correctly timed? Perhaps both of the sprockets are out one tooth. I've worked on more than a few other brands finding the T-belt off one tooth - they idle OK, seem to run acceptably, but have no power and and just "soggy" feeling. Given all you've done, it will cost very little to confirm correct cam/crank timing. SRK You know... this is something I was thinking about too. the owner spent a TON of money over maintaining this car, and it was odd that he spent the money changing the timing belt and then a few months later sold the car. I was thinking maybe the toyota dealer he went too didn't do it properly. I got the spark plugs changed recently and it was written on the receipt checked timing or something of that nature. Is there a different timing for spark plugs or is checking the timing a standard thing to do after changing spark plugs? How does one go about checking the cam/crank timing and how much does it cost roughly? Do let me know, and thanks for the replies guys! Edit: I guess cam/crank timing is different then ignition timing. How does one check the cam timing, the LS400 looks complicated, would it have to be taken apart?

Yes I'm calculating driving a full tank (reset the miles, calculate the gallons etc. by empty tank I mean I filled 19 gallons so not one hundred percent empty but does mean my fuel gauge is worki g because it does have space for thag much fuel) and so roughly 205 miles driven and 19 gallons gone (every time I gas up is always a fill up). So varies from 9-11 mpg in the city. 25 on long trips and if I drive an hour on the interstate and mix city well. That's coming to about 15 mpg. I drive about 25 miles short trips after filling up over few days and needle moves. Then after parking it. Needle has moved a lot more! No one is stealing gas from me and no leaks. Probably 65 percent of my trips are about two miles back and forth to office maybe twice a day and sometimes a bit more for food local shopping. I never let car idle. I do notice when the car is started first in the morning on cold days it's as if the engine is frozen. I give it gas but the car doesn't want to go its as if I am pulling a trailer and the sound isn't so great. It feels like crap! I use 5w30 thought of switching to 0w20 or something maybe to get better flow and warm up faster or get a higher temperature thermostat I have a feeling mine might be opening too soon but none the less on auto climate heat barely starts coming in 5 minutes and about 13 minutes from start the car seems like the engine has reached operating temperature.

Blah, drove to Ohio a few weeks back (five hour drive) averaged 27 mpg. In the city, I'm getting around 9 mpg right now.. Yes, NINE! I took it to the Toyota dealer, they checked the fuel trims and said everything is 100% perfect. I'm stumped at this point. The car drives like a dream, (slightly bit noisier than our other two LS400's, like the resonance is off). Its pretty bad when the gas tank is on E at 230 miles. No idea why a car would perform flawlessly, get wonderful gas mileage on the highway, but totally klunk out in the city.

I'm pretty sure the engine and transmission are also "sealed", but they still degrade! And Brake Fluid.. well its like honey in color when its new/fresh but after a few years it becomes black, so something is going on. I don't know why, the maintenance schedule says to change it every so often, but many dealers are saying "its a sealed system, we never change it unless major brake work done".

I find the best price for oxygen sensors, and quality, the densos on amazon are pretty much literally a perfect fit just like OEM

What year is your LS400... are you sure this isnt about that engine ECU problem where at 45 mph it feels like your engine hits something, like a super rough shift boom? Very common problem on the LS400 specially 1995/1996

Way to key in your advertising their buddy, on an old thread, they surely have gotten their car open 4 months later. My suggestion to anyone with a Lexus key problem is to make sure you have a spare key somewhere. For pre-97 lexus, find a lexus dealer, ie lexus sewell, they are good. Send them your ownership documents showing your name and vin number and for 59 dollars they will have an original lexus key cut for your car.

Replacing the ECM is usually the last action in the diagnosis in anything the ECM controls when it comes to diagnosing through the factory books. Diagnosing the ECM is tough but is done by somewhat of a process of elimination. At first I had a slightly rough running car. I replaced the plugs, wires, caps and rotors with OEM parts. The car seemed to run slightly better but still somewhat rough and I just thought "Whatever..." Over a year later the car starts really running like crap and throwing a CEL for the engine coolant temp circuit malfunction. I replaced the engine coolant temp sensor for the ECM to really no avail, it still ran terrible. I have a Lexus tech buddy that works at a Toyota dealer and I was at whits end with the car. The next thing I thought was O2 sensors as they are original on 230k miles. We hooked the car up to a scanner and the O2 sensors appeared to either be going bad or the cats getting very very weak as the line should have been mostly flat and its was jumping a little at idle. Then he pointed to 2 mid 90's Lexus's sitting in the parking lot waiting on ECM's and we agreed that they seem to have issues with age and miles. We removed the glovebox and checked the reference voltage, which should be around 5V I think. It was over 8V. The ECM measures temperature by resistance that comes from the temp sensor on the engine. To get a reading for the ECM it needs a reference voltage on each temp. circuit while the logarithm is calibrated for a certain reference voltage, usually around 5V. If the reference voltage is different from that then the ECM is either going to think the car is too hot or too cold. My ECM thought the car was too cold and that it was never warming up. The ECM keeps throwing fuel at it because it thinks it is cold but it never sees it warm up. This is why it only ran good cold and terrible hot. I replaced the ECM and it runs better than it did with the original plugs and tune-up parts. I'm not saying this is your problem but you wouldn't believe the fuel mileage my car got with the bad ECM, if it would stay running... Lucky you were able to sort your problem out, most people would throw the car away rather than spend time and money on diagnosing it. The thing with mine is that it runs butter smooth 10 min after starting from cold, no shaking, no stalling whatsoever, I mean it drives great powertrain wise! I hardly know the car is running and it has great power and feedback. Oh well, maybe for its age mine is just how it is. I drove 150 miles the other day on the highway and got around 21-22 mpg with the ac on, driving at 68 mph the entire way. Hit city driving and falls back down to 11.4 mpg as usual! Guess Ill have to live with it for now until something acts up!

You make the best point on here. That's the one thing I always think about and fear is most likely the culprit here! But its kinda hard to diagnose a bad ECM because technically it isn't "bad" but not working "properly". Are they easy to change? I guess it wouldn't hurt to get one if can find a good deal on one somewhere. Because sometimes outta the blue, the car runs SUPER smooth and quiet and gets great gas mileage, and then it goes back to being its bad self again as if its a loose connection or wire somewhere. I've spent a ton on this car already and plan to drive it another 5-7 years at least, I don't see what other item could be causing the problem except the ECM as well. Otherwise its a useless chase and people keep saying I must be driving incorrectly or saying thats just how the mileage is, makes me wanna say "here take the car and drive it yourself for two weeks and tell me how you feel at the end!". But just curious, if the ECU/ECM is bad, wouldn't it show on the fuel trims?

haha yah, its an idea but its shifting fine. On the interstate around 65 mph I'm around 2000 rpm roughly. My LS430 gives exactly the same temperature indication. This is absolutely perfect! Jac Thats good to know, thanks for the reply! I guess its down to just a vacume leak somewhere now

Half a tank... 104 miles driven. I know some may argue that half a tank doesn't mean exactly HALF a tank, but I bet everyone shows at least 150 minimum when their tank is showing half full, I know its not an "exact science" indicator. But after driving for 15 years I can honestly say after a while you get to know how cars and the fuel meter works, and I can honestly say I've never driven any car with the gas tank half empty at a hundred miles. And yes, I fill up exactly the same each time at the same gas station, I let it stop by itself when it gets full. (and yes I've tried other gas stations, same results). And when I go to fill up this half tank, it will take me around 10 gallons to get full again. I've noticed even though its a 100 degrees F today, that is as hot as my engine temperature shows, is that normal, because I've seen some LS400's show a "half" a notch higher than that.

I'm doomed. Literally at the halfway mark on the fuel tank and just 100 miles driving for this tank (100% city)! If I drive on the highway It will be like 220 at the halfway mark though, which is ok. Say what you want too, but that is completely wrong. I almost thought its quite possible my tripometer was inaccurate, or my fuel gauge is off, but when I go to fill it up surely enough it has plenty of space. At this point in time I'm thinking I might have a fuel like, but no smell or anything visible. City mileage at 11mpg is just disgusting =( No one can tell me my 96 LS400 is as bad as these guys http://autos.yahoo.com/news/greediest-guzzlers.html The elusive search for a cure continues

According to your phone app, you filled your tank 6 times in 424 miles and 16 days. Why are you doing that? Try calculating fuel mileage over full tanks of fuel. Fill up and don't buy gas again until your gauge falls below 1/4 tank. There is too much variablility when a tank is topped up every 50 to 75 miles to accurately calcuate fuel mileage. Even then, don't calculate you mileage by individual tank fulls. Calculate your mileage over four or five tank fulls. Contrary to popular wisdom, I suggest occasionally running your tank down until the low fuel light comes on. Some say that can cause problems from debris clogging fuel filters but I've been doing that for decades with never a problem. In some of the European cars, I've often let the main tank go dry and let the engine start missfiring before activating the fuel reserve switch. IMO, doing that gets rid of the crud and water and keeps it from building up and floating on top of the gas in the tank. Yah, I filled it often. I usually fill it around the halfway mark, don't know why. Will ride it until its all the way empty and let you know how it shows then.

You seem to still be talking in generalities rather that specifics. Keep detailed track of your fuel mileage over a number of tank fulls and then report back. Trying to determine what gas mileage you are getting in city driving vs. what you are getting in highway driving is very difficult. If your father consistently gets 26 mpg in highway driving in his 95 4-speed transmission LS400, I'd call it a miracle. The very rare times I've exceeded 26 mph in my 2000 5-speed LS400 have been on long (e.g. 700+ mile football weekend) trips mostly on cruise control where I did viturally no low speed driving other than to pull off the interstate, fill up the tank, and continue on down the interstate at speeds within the speed limit, in low/no wind conditions, in a lightly loaded car carrying only two people and a couple of small suitcases. Even a little low speed stop and go driving or a head wind makes my overall average fuel mileage plummet. Disregard your iPhone app, buy a small booklet and record every fuel purchase, date and and odometer reading for the next 1,000 miles. I've done this for about 700,000 miles of driving and can attest that doing this eliminates guessing. The iPhone app is the same thing as a booklet, it records every fuel purchase, date, odometer reading. I enter the odometer reading, indicate that I filled up, how many gallons the fill took, and I get my mpg. Its literally the same thing as doing it by hand. I can honestly say that I am getting 11 mpg and this has been going on for 9 months now. I can honestly say that highway mileage is good, 20-23 is reasonable. But 11 mpg city just is horrible no matter how you put it, I'm literally not exaggerating, or doing anything wrong in recording or driving habits. Hell, our old 87 420sel with 290,000 miles on it, which isnt maintained at all is getting 14-15 mpg in the city! I've come to the conclusion it could be the thermostat or some air leak though. I don't care if its normal mileage I'm getting but I think the extra fuel is damaging my catalytic converters slowly and oxygen sensors and I had to replace those because they both went bad at the same time 2000 miles ago, so worried about the unburnt fuel. I thought changing the oxygen sensors and spark plugs would prevent them from going bad again but the mileage still hasnt improved. If I drive on the interstate anywhere I can get 220 miles until reaching half a tank, and in pure city driving I get 100 miles at half a tank. And I get 9 mpg in the winter, and 11 mpg in the summer with the ac on.. *sigh*!

Here is my current printout, they didn't give me a before printout, but this is the current settings they gave me. I don't know how to decipher it so if you can tell me if it looks ok?

Per Randy's lame comment, the condition of suspension components has virtually nothing to do with fuel economy - unless your car is bouncing all over the road. I'm a scientist and I'm not seeing much good data here. Fuel economy can be accurately calulated only over a substantial number of miles and tank fulls. And 23 mpg on the highway is right at the EPA revised estimate. Those with 98-up LS cars have the advantage of having an instant mileage readout which can show how horrible fuel mileage can be for these cars. I watch my fuel mileage range between about 5 mpg and 15 mpg when in stop and go traffic but that's normal. I'd be more interested in what your gas mileage is over 1,000 miles. If it is in the 18-19 mpg range, that is normal. I'd say over a 1000 miles I'm averaging about 14 mpg in the city at best. All winter was getting about 9 mpg in the city, and 11 mpg in the city during summer right now. If I go on the highway I might get 20 mpg max. Only on one lucky day I was able to squeeze 25 out and that was a miracle, but other than that nope. But my father has a 95 LS400 which is almost identical to my 96 LS400 and they get 19 in the city pretty constantly and about 26 on the highway no problem. They have never gotten 11 mpg like I have gotten, and I am consistently getting 11 mpg unless I get on the highway to make a trip, than my mixed mpg is about 16-17. I would LOVE to get 16-17 mpg in the city! If I fill my gas tank up fully and just start from scratch on a 2 hour trip averaging 55 mph only THEN I'll get 25 mpg. Otherwise regular interstate driving I'm getting 20 mpg =( Something is wrong for sure because makes no sense another LS400 we have that is actually much less maintained gets twice the miles per gallon I get.