Slvr99LS

Mike, in the event it turns out that it is the ballast at fault rather than the bulb, on the 1998 - 2000 models with HID option the ballast is located directly underneath the entire headlamp assembly and is attached to the bottom. In order to gain access to it the whole lamp assembly has to be unbolted from the car, which doesn't look all that difficult. Due to the completely ridiculous OEM replacement costs, as an insulator against future 'wallet-shock' (and having never owned a vehicle previously with HID lamps), I bought a complete spare assembly with some cosmetic flaws on eBay not too long ago in case of an occurence just like you're currently experiencing. Curious how you make out with this particular issue since from what I've gathered it apparently isn't all that common for them to fail - please keep us posted.

These guys are spot-on... it's the strut bar/rod bushings. I just did mine on a '99 and it made a world of difference in everything from steering to braking, not to mention finally being rid of that aggravating 'clunking'. It's a decidedly un-Lexus-like sound. '84 Chevy Cavalier... maybe. Anyhow, I opted for the less costly, though far more labor intensive method of replacing just the bushings rather than simply swapping out complete new bars. Hey, times are tough and those bucks add up. Using a lift is highly recommended, if not mandatory for this job. Once the bars were removed from the car, (you'll need an impact gun or some good sized breaker bars for some of the bolts/nuts... and a torque wrench for reinstallation) cut a thin slot through the rubber and the outer metal shell of the old bushings with a Sawzall and they pretty much fall right out with a couple quick whacks with a hammer. Or a press would certainly do it, but I didn't have one handy at the time. It was clearly evident upon close inspection just how far the rubber had deteriorated after 10 years. These bushings are under a ridiculous amount of stress with this particular suspension design. Once you've studied the geometry, it's a wonder honestly that they last as long as they do. After everything I'd read on the forums prior to undertaking the job, I figured a press would also be required to get the new ones driven home, but it fortunately wasn't the case. With a good friend laughing, shaking his head, and assuring me I was nuts to even try it (I take that as a challenge).... I had the new bushings chilling in the freezer for a few hours, plus made sure to carefully lightly sand clean both surfaces. Then, using a simple large bench vice and a suitable diameter pipe to carefully push against the outer shell of the new bushings.... and.... they're in. Not bad at all. The laughter ceased too. :) After working out the procedure for doing one side, the other side progressed far more quickly. The lower strut mount does have to be unbolted from the hub which was no problem with that corner of the car supported. A small scissor-jack worked like a charm and also allows for precise height adjustment while you're realigning all of the bolt holes - sometimes easier said than done. Assuming you want to do it yourself, I'd say a realistic figure would be 4 - 5 hours labor total including futzing around with removal of the old bushings. In retrospect, to do it all over again, I'd likely recommend just buying the complete new bars. That would make the job almost a cakewalk. Hope this helps.

For what it's worth, I was glad to read your post. Why? Because in many ways my '99 acts EXACTLY as you describe your '98. It's a higher mileage car (well over 100K), purchased pre-owned and was primarily dealer maintained since new. On an ice cold start, if the engine isn't allowed any time to warm and is driven immediately, the initial shifts of the transmission... particularly the 2-to-3 shift... is delayed until a much higher speed than 'normal' for a given throttle position. I believe you're correct in that it has something to do with the ECU programmed warm-up. If the engine is allowed to warm first before driving, the shifts occur normally, although they are notably firmer when everything is still cold. I have also noticed that extra nudge you mentioned, particularly when shifting from reverse back to forward. I recall my '92 LS doing the same thing when cold, but it was less noticeable for whatever reason. Replacing the transmission mount did not affect that particular aspect, but it did take out a noted harmonic vibration from the driveline. I've also replaced the fluid because I wanted that bright red color back rather than dark brown (drained and refilled the pan several times over the last 750 miles or so) which definitely smoothed the overall shift quality, although it's admittedly "too smooth" for my liking. Coming from a performance vehicle background I'm aware that all that shift overlap the engineers have designed in their quest for smoothness causes clutch wear. Unfortunately I haven't found any aftermarket product out there that'll allow recalibration of Lexus transmission programming. Personally I'd prefer the shifts be somewhat quicker all through the range and I definitely wouldn't mind a mild 'bump' indicating positive engagement of the next gear. It's a very satisfying feeling once you become accustomed to it, the transmission clutches will last far longer, although I realize it goes against the grain so to speak of what the car was designed for.... which is ultimate luxury. A leather couch wafting down the road on 4 wheels. Some would simply say, if you wanted a 4-door sports car, buy a BMW... and I almost did (740i), but the Lexus reliability factor ultimately swayed the decision. In any event, just wanted to convey that having never driven another '98 - '00 model, I can confirm that much of the behavior you've noticed with your transmission would appear to be consistent with my experiences with the same car, with the possible exception of downshifts, which I believe should be virtually imperceptible when coming to a stop. For the record I was nervous enough about selecting fluid after all that I'd read that I did go with the 'correct' Toyota T-IV purchased at a local dealer, although I did recently do another pan drain and used Amsoil Universal Synthetic which claims T-IV compatibility. Didn't really notice much of a difference with approximately 25% of the fluid now being Amsoil. Hope this helps in some way. Appreciate your post. P.S. Curious, but what did the dealer charge for all of that work you had done when you first bought the car? Thanks again.

Think everyone might've missed the the real reason why this car was done up like this in the first place. It's actually quite practical. Ya see, you never need ramps or a lift to do anything... it'll never be a flood car even in Monsoon-strength rains... and it doubles as a comfortable 250HP V8-powered off-road vehicle with plenty of ground clearance in a pinch! See? Suddenly it all makes sense... B)

Aquatic

Hey J, I'll be getting back to the intent behind the original post shortly and proceeding with my mileage tests, followed by the results. I've had my hands completely full with this car over the course of the last month (much of it documented here on the forums in the hope someone could benefit from the experiences), so much so that it's single-handedly diverted my attention from other projects which are always on the burner. Anyhow, you're probably correct - 35MPG is definitely asking a lot from the car, but that was the intent. I've spent most of my life pushing the boundaries, and this is no exception... though it's definitely less likely to cause serious injury. :D Regardless of whether it achieves the 'magic number', it's worth the attempt in my opinion. The lessons learned from it should be applicable to any year/make/model of vehicle. I've never previously attempted anything like this, nor did I care to. I'm a motorsports nut who really never gave fuel economy much thought... what a boring topic, at least on the surface. Then you start to dig into the engineering aspects and psychology behind it... and... it's intriguing. Guess one could say I had an epiphany of sorts. This past year or two has seemingly been a really pivotal point in our global economy. I took it as a wake-up call that did more than vaporize the 401K. Not trying to divert the thread with a political statement, but watch the cost of a barrel of oil soar through that $100 mark again (taking the price of gasoline right along with it) and you'll see a huge jump in national interest again in this sort of efficiency-related experimentation. So why wait? Be ahead of the curve. Definitely isn't any harm in it other than the road-rage it might instill in others on the freeway because you're actually doing close to the speed limit. Need a bright flashing neon sign that says: "just testing" to avoid being rear-ended at 70 by the lady in the Dodge Caravan who's late for Jimmy's soccer practice. B) So far the mileage with this LS has already picked up dramatically from just fluid and filter changes, along with moderately increasing the air pressure in the tires. The results were so encouraging that it led me to write the OP. I definitely never expected the level of feedback from this thread that it has received, and I appreciate everyones time and thought-provoking insights. Awesome to hear that your car has gotten 30+mpg already. That's really encouraging. More to come.... P.S. I've also decided against any type of 'hypermiling' attempt at the moment... seems that's more of a test of a drivers skill and use of various controversial techniques than a realistic display of a vehicles mileage capabilities in 'real-world', everyday driving. I can see where it could get addictive though and take over your life - "I got 49mpg out of my diesel Jetta... I just KNOW I can get 50~!!"

Actually Curious, the GM throttle position sensor IS a perfect example... a perfect example of the point I was trying to make - that all is not always as it seems, a component can experience a partial failure, and not every sensor related issue will throw a code. Are we in agreement on at least those points? You're also understating how significant the temp sensor input is to the overall fuel curve. In many of our racing vehicles (most are still street-driven as well), a low-temperature thermostat is almost always installed (generally 160F). Factory 195-degree thermostats aren't even fully open in most cases until 210-215... heck, some vehicles don't even turn on the secondary electric cooling fan until temps reach more than 230 degrees fahrenheit! Not exactly conducive to making consistent power. Sure does thin out an oil too. We won't even get into the other detrimental effects of high coolant temperatures on an engine over long periods of time. Legions of gasket failures are but one byproduct. But for drag racing, the heat-soak between rounds is so significant, it's been proven to be worthwhile to pack the intake down thoroughly with ice. We're after cool air there... cool air = denser air, which means more fuel can be added and greater power output experienced for a given set of conditions. The lower coolant temps also signal the ECU to deliver a slightly richer mixture, and not just at WOT throttle settings. A very simplified model of how things react in the real world, but for this discussion, it works. We won't get into adiabatic engine theory here, as that's a topic for a potentially whole new thread. Suffice it to say, factory engineers are after very low emissions, and maximized fuel economy (meet CAFE standards - easier said than done). They also have to walk the fine line between longevity, power output, and the aforementioned emissions and fuel economy. Not an easy job. Sorry you don't find my theory particularly compelling, but I haven't heard anyone provide a better one yet. When one is given that presents a valid scenario, I'll give it the strongest of consideration. I recognize your desire to discount the observations I've presented, but we're also potentially talking about a whole lot more than "a few microns" worth of deposits here. I've seen rust/scale/corrosion more than an 1/8-inch thick in older cooling systems. I've also seen complete system failure. Basically plugged solid. Stuff turns to mud for lack of a better term. Ever seen what some supposedy 'extended-life' coolants like DexCool can do to a cooling system? There's been pending class-action litigation out there on this very topic for years. Try Googling "dexcool failures" and prepare for a full nights worth of reading. Having been around the block more than a few times... I stand by my assertions. Perhaps your maintenance regimen is superior to that of many others. I did note you own a much newer model of LS, so it's pretty clear your 2004 model is unlikely to suffer many of the maladies of an 18 year old vehicle for example. The majority of owners who've experienced dramatic improvements by replacing the coolant temp sensor are those with first or second-gen cars. Most have well over 100,000 miles. Many have 200,000 on the clock.... some, 300K. Probably safe to say most are riding around with the original, factory installed sensor still onboard. As previously stated.... I continue to believe there is something to it.

nice....any chance of you doing a pictorial or a diy on this when you do the mounts? i wish i had asked you to do one on the tranny mount as im wanting to do this but im unsure of how difficult it would be Hi Sakataj, about 2 weeks ago I posted a DIY on the trans mount on an LS (very similar) with photos of both the old and new mount. It fixed a significant part of my vibration issue as well and I highly recommend replacing it. I'll try here to attach the link: http://us.lexusownersclub.com/forums/index...mp;#entry371875 I realize it's a somewhat lengthy read, but for clarity I wanted to provide the whole story. Hope it helps...

I believe there is validity to both sides regarding the sensor issue, but it may be unfair to term it 'junk science' just yet, as I have a theory. The one side of the coin is, "don't waste $$$ on frivolous parts that aren't bad." Fair enough. I believe most of us likely prefer saving money over intentionally wasting it. But, it's definitely worth mentioning 'Jcrome' certainly isn't the only long-term member of this forum who states he saw a substantial improvement in fuel economy and overal responsiveness by doing nothing other than changing out this mysterious coolant temperature sensor - there have been plenty of others. So let's not dismiss their findings so quickly. They have nothing monetarily or tangibly to gain by starting or perpetuating a myth, right? I'd say this forum is generally filled with helpful, good-intentioned people. But, that's not to say the topic doesn't warrant further thought and consideration. My theory... and it's a fairly simple one involving thermal conductivity, goes a little something like this: Anyone who has ever viewed the inside of an older, well-used radiator has seen the tell-tale accumulation of crusty rust and scale deposits. Give it enough time, mileage, and particularly anti-freeze neglect (lack of periodic flushing and replenishment), and the entire cooling system obviously starts to suffer from an efficiency standpoint. The transfer of thermal energy from the hot coolant to the radiator is no longer anywhere near as effective. In extreme cases, the engine may even eventually overheat on a warm day with no clearly obvious cause. Now... bear with me here. This particular sensor is living in a hostile environment, projected into the coolant flow at the intake manifold for the life of the engine. With suitable age and mileage, a similar insulative crust may form on it which could easily be giving false readings... and those readings would tend to be low, i.e. telling the ECU the engine has not reached full operating temperature, thereby providing a richer mixture at virtually all throttle settings. Voila - a significant loss of fuel economy, and no check engine light! The sensor could easily still test within accepted parameters. Again, I'm sure I'm opening the usual can of worms... and I'm prepared for the backlash that comes with a differing view, so let's be adults here. It's only a theory, but it seems in my pea-brain to hold water. No pun intended. And for the record, I just spent substantially more on an air filter than the mentioned cost of the aftermarket replacement version of this temp sensor. Could thoroughly cleaning the sensor rather than replacing it make a difference? Perhaps - I haven't noted where anyone has attempted it, since it's so inexpensive to replace. Anyone? Over the years as a tech, I've had other engine control related sensors give problems without triggering codes and still measure well within stated tolerances. Perfect example is a GM TPS (throttle position sensor). Basically just a variable resistor sealed in a plastic case with a pair of conductive carbon tracks inside and a pair of metal 'fingers' which sweep as the throttle valve opens and closes. In a nutshell, it tells the computer where your foot is on the gas pedal. I've had several of these, on different cars, cause driveability problems without ever registering a code. Their voltage output to the ECU also fell within specs at both idle and WOT, but small virtually microscopic breaks or wear in the carbon tracks (particularly in the mid-range where most driving time is spent) were causing suitably inconsistent output from the sensor that it drives the ECU crazy. Swap out the sensor and the symptoms vanish like magic. And that's just one example. Simple facts: things do wear, none of us knows everything, and no technology is perfect. 'Nuff said for now. Back to the temp sensor - beyond mine, any other theories out there other than to just dismiss the whole thing as wishful thinking? Not stating for a second that everyone should just go ahead and replace theirs, but I believe there is something to it.

In the quest for maximum fuel economy, as well as enhanced engine performance, one of the simplest, least costly places to look is your air filter. Shown below is a picture of the actual filter element recently removed from my LS. Pretty easy to figure out which is the old, and which is the new. Lord only knows when the last time that thing was changed! Most amazingly, this was a Lexus dealer-only maintained car for at least 80+% of it's life (I have the maintenance records). Perhaps even factory trained technicians don't customarily check every customers filter if no problems were reported. Worth bearing in mind. This thing is so nasty you could grow mushrooms from it (see below). Upon close inspection of the filter there are dead bees, other insects, leaves, grass clippings, sand, and plenty of unidentifiable grime and debris all lodged in the pleats. It certainly did its job, as the engine intake side was still remarkably clean. If the factory filter didn't have such a large surface area I suspect this amount of contamination would've affected performance and mileage long ago. And it only takes 5 minutes to replace. On another note, this evening I replaced the original sway bar bushings to help restore the factory ride quality. The interesting part is that the OEM Lexus bushings come completely coated with a thin, dry-film lubricant to help prevent squeaks at the body-to-bushing, and bushing-to-swaybar interface. I'd never seen that done before. Indicative of the great attention to detail the engineers lavished on these cars. Briefly contemplated firmer aftermarket polyurethane replacements... but nope - decided on keeping it all original. Permission to vomit granted....

Sam I Am.

Whew is right! Good stuff though, and very interesting information on how they keep those irreplaceable warbirds in the air on todays fuels. I actually did take note of the 100-octane low-lead fuel available at the airport last week, but didn't realize there's nothing else available. On another note, curious why with all that's been stated in this particular thread, you and your wife don't run 87 octane in your cars? Personally, I'll stand by my prior assertion and continue to pony up and pay for the 'good stuff'. As another post suggests, I'm sure the big oil companies appreciate the pad to their quarterly profits. Shifting gears here and getting back to the core intent of the thread, another LOC member mentioned here the term 'hypermiling', and I may have to employ some (but definitely not all) of their techniques to achieve 35+mpg from the Lex, but yes I do believe it is a very realistic goal and can be done. One commonly used method is called P & G (Pulse/Glide) which is apparently very effective when applied correctly. In a nutshell it involves accelerating to a given speed, coasting for a period, then repeating. Hills and valleys can also be used to ones advantage. During 'coast mode', most modern fuel-injected vehicles completely shut off the injectors. Spark continues, there's just no fuel there to burn. I do know my instantaneous mileage on the trip computer goes immediately to '99.9' when the throttle is lifted. If you throw the car in neutral and allow it to coast, fuel is still being burned at idle, although you remove the parasitic drag of the engine itself so it may or may not be a wash on that count. Some experimentation is in order. I doubt I'll be able to do it safely on the freeway without getting plowed by a Peterbilt and/or pizzing off plenty of people, but for rural driving on lightly traveled backroads, seems it works very well. Either way... like I've maintained all along, it's going to be fun to find out. I've spent a lifetime going fast, what's wrong with a few days of going slow? I'm not looking to get crazy with this, just find out what's possible with relatively minimal effort and expense. Toward that end, here's some cool info I found on Wikipedia: http://en.wikipedia.org/wiki/Fuel_economy_...ng_technologies Straight off they mention low-friction lubricants, which is a great starting point I'm already pursuing. More to follow...

Aarman, thanks for the vote of confidence... seems you're the first! In less than 24 hours I've been told it's a fantasy, I'm dreaming, to strip the whole interior out, told I need lessons in thermo-dynamics and chemistry, suggested I burn 87 octane (why not 85 then??), who needs A/C, power steering, etc.... which all just made me :D ear-to-ear of course. Man, I love these forums! Interesting that you mentioned 'hypermilers', because I'll admit I have done some reading toward that end, and will concede they were part of my inspiration in the first place. Apparently the doubters far outweight the believers.... which naturally just inspires me even more to succeed. I'll pass on tailgating the stone-throwing 18 wheelers, thanks. And for the record, there will be NO modifications done to the car. Despite the suggestions to the contrary, the Nakamichi stays. The 225mm wide Michelins stay. All the seats... those stay too. And just so no one crys foul, I'll even eat a huge dinner before attempting the record run. B) I'm genuinely serious about this, even if no one else seemingly is. Bet if gas were $5 clams a gallon right now this would be the #1 read thread on the entire forum. This same time last year some nutjobs on eBay were paying $7,000 for a 14 year old Geo Metro with a 3-cylinder gerbil mill under the hood because gas costs seemed to be escalating with no end in sight. 8-year old Honda Insights with 100K+ on the clock were selling for what they went for brand new. People were legitimately panicking. How quickly we all seem to forget though. Fact is, we have a finite supply of fossil fuels and it unfortunately won't stay cheap (a relative term) forever. In the meantime, I'm having some fun with this. Thanks to all who've already taken the time or enough of an interest to follow along.