oldskewel

Thanks. $113 for BOTH mounts? Hmmm.... well I think when I got a quote from them it was $90 each for the mounts and $59 for the tranny mount. Maybe they dont like me? lol. Oh I notice you have a 99 LS400. Surely they are not cheaper for newer LS??! One would think they would be even more complex/advanced? That would be my luck though. :( I will try again. That part number for the motor mounts is the same as I put on my '91 early this year. Paid $92.67 each with free shipping. The Trans mount for the '91 is 12371-50010, paid $57.05. Yes, the trans mount changed, and got cheaper on the newer one (-50060). If that $113 for both quote is real, it is a great deal. I replaced them all myself. The trans is easy. The engine mounts are harder. Definitely do not go with anything other than OEM on this. I can't imagine how a "universal" part would work. It is an extremely tight fit. If anyone's looking to do this themselves, I followed Glenmore's instructions, with the following deviations: I used a pivoting socket wrench (having this tool was critical in making it easier - this is like a standard 3/8" drive, except the handle pivots at the head) with a standard-depth 17mm socket on it to get the upper nuts on the mounts. Passenger side first - used craftsman 17mm open end wrench with big long second wrench to add leverage. Came easily. On driver side, the pivoting socket wrench was essential. I removed the wiring harness + PS line as instructed, but none of the other stuff (did not touch AC, no PS return hose hold down). (all this, not only because I'm lazy, but because I did not want to open any cans of worms along the way) I did remove air cleaner, etc. since that seemed to be getting stressed as I lifted the engine carefully. Removed both wheels and splash pan cover for clearance. I removed the oil filter (and did an oil change), but that may have not been necessary. Lowered crossmember nuts until only about 2-3 threads were engaged. Everything else was as Glenmore's instructions said.

The above fits with my understanding as well, except maybe not 100% with "The engine runs at its optimum efficiency using the higher octane." If the engine is designed to run on 87 (which the designers would do to provide all the benefits of lower octane gas, sacrificing pre-detonation resistance, resulting in an engine with less peak power), it can run at optimum efficiency on 87. If it were to run with 91, there is still no risk of pre-detonation, but the fuel components that inhibit predetonation (by reducing the combustibility of the fuel) mean the fuel does not burn with the same speed and energy of 87. ==> higher fuel cost in exchange for lower mpg and no increase in power. I think there's a difference between how a Ferrari would respond to 87, vs. a Honda minivan. The Ferrari engine would be designed to provide max power per displacement (, weight, etc.), with a very careful _mechanical_ design and engine management to match. Surely it would require high octane, and dropping down to 87 would cause the engine management system to move far away from the tuned operating point that the engine designers crafted. It would protect the engine, but in addition to a drop in peak HP, mpg would probably drop, and it might not perform smoothly, etc. Ferrari could of course design an engine that would perform acceptably well with 87, but to do so would compromise the high peak they strive for, and their customers don't want that. Same reason they don't have rear seats or a trailer hitch. The Honda engine (like the 3.5l V-Tec we have) understandably seems to be designed more for flexibility than for high end output. E.g., one cool feature is that it will shut off one of the two intake valves in each cylinder at low engine loads (idling, or cruising). With only one intake valve open, the fuel-air comes in faster, creating better mixing and more complete combustion ==> better mpg and lower emissions. Variable valve timing as well. In this car, it recommends 91, but gives a spec for 87 with a reduction in peak power of 5 HP. I expect that since this engine has such flexibility in the mechanical design, the engine management (injection, timing) can handle the 87 far better than the Ferrari could. Ours seats 7 and has a trailer hitch. I expect the LS400 is in between these examples, which is why this is an issue. I bet there's not much discussion about what octane to use on the Ferrari message boards. ;) I bet the hot issue right now is how to get their money out of their hedge funds that just closed up.

I looked into things several years ago, and the above is pretty much the exact conclusion I came to as well. So, when friends ask me for advice on this (as they often do after they've bought a new car and want to do what's best for it), I tell them that if the manual says their car works with 87, they might be doing worse with 91, even without considering cost. Lexus LS400 of course may be different. So far, I just put in 91 in my '91 (not just because it's got a ring to it), since that is recommended, and I have not yet been convinced the engine management can handle 87 without problems, but for example ... for my 1985 911, it requires 91 (92 actually, but can't get it), and being just old enough, the engine management can't accommodate lower octane. So if I drive aggressively with 87 in there I could damage the engine. In this case there is no option - I use 91. Once I filled up with 87 by mistake. I drove like an old lady for half a tank to protect the engine, then filled with 91. I noticed my mileage increased by about 5% for that half tank, but it's hard to tell if it was the low octane or the granny driving style that did it. To tell for sure, I'd have to drive granny style on 91, and I'm just not willing to do that. B) for my wife's minivan, it says it will get 210 HP running on 91, 205 HP running on 87. Clearly 87 is OK, so we use that, giving up 5 HP for all the other benefits. To potentially launch on another tangent, I never ever (now that I know) use ethanol. If nothing else, it has about 2/3 the energy content of gasoline, so if the fuel is 15% ethanol, it's like getting fuel with 95% (85 + 15*2/3) of the energy in gasoline ==> 5% loss in mpg. There are engine-life issues/doubts beyond mpg. If the fuel has ethanol in it, there will be a sticker on the pump saying so. Ed

I'm not sure if this is news, but it was news to me when I found it just now: http://www.toyodiy.com/parts/g_U_1991_LEXU...L-AEPGKA_2.html (that is for my 1991 LS400, but of course you can go upstream and pick what you want) Looks like a good source for part numbers, and maybe more stuff down the road. Hope someone finds it useful. I have no affiliation with the site. Ed

I'm working on some brake issues myself that are proving tough to figure out. I rebuilt the calipers several months ago (one needed it, the others were for good measure). ~160k on my 1991 LS400. How common is this need for a MC rebuild? At what mileage is it commonly needed? Thanks, Ed

Would this be a good job for brake cleaner? My understanding is that it is a good general purpose solvent, with the important feature that it leaves no residue (unlike WD-40) but can be sprayed precisely with the little red straw. Could you spray brake cleaner in there (better flow than if trying to drop some alcohol in) to wash the bad stuff out (gunk, WD-40 residue, old graphite residue)? Since the fluid is likely to be conducting, with all the suspended particles, while it is washing stuff away, I'd be sure to disconnect the battery prior to trying this. When all done, if you can get it clean, adding some graphite powder at the end would be good. Ed

One more thing ... Welcome to the club!

Couple of quick ideas before the experts chime in. - These problems might not be related. - Any time an electrical problem shows up, it seems that the trunk wiring harness is the first thing to check. - Regarding the "stuck" throttle, does it really hold _exactly_ 52 mph or 73 mph or whatever (as cruise control would), or does it just hold the approximate speed for a little while? My thought on the auto-revving when in park (based on other cars I've had) is that it could be caused by the Idle Air Control Valve (not sure the Lexus calls it this) sticking. These are often near the throttle body. You can try to see if tapping it with a wrench while it is revving changes the revving (e.g., stops it). If so, it may be ~clogged internally, and the tapping allows it to move. In both cases I've had with this problem, I've found that simply removing the IAC valve and cleaning it out (no need to disassemble it) with brake cleaner (any similar solvent should work) fixed it. Good luck, Ed

Great information. I've filed this away. Thanks! I'd like to echo that suggestion on not using a pickle fork. I've seen many instructional posts that say you'll need new tie rod ends when you replace the lower ball joints, just because the pickle fork will ruin the rubber. Not true. When I did mine, I used a screw-type puller that worked perfectly, probably easier than a pickle fork, and the perfectly-good tie rod ends were re-usable. Ed

Thanks!

From the forums, I'm aware of all the problems the trunk wiring can cause. I have no symptoms right now. I'm guessing it will be better and easier to do something now (to loosen it up somehow?) as a preventive measure? Right? What should I do? I have a 1991 LS400. Thanks, Ed

Well it was. When trying to use pliers to work it free, it would crack on the surface. Yet enough of it would hold together, and the sub-surface parts were almost like they were glued on to the reservoir pipe. I quickly conceded that it would be destroyed in the removal process, and it still was very difficult to remove. Hope yours is not like it.

Sounds easy, but all it takes is for one of those hoses (or bolts) to be a PITA to make the whole job a PITA. On my 1991 LS400 (~160k), I needed to remove the PS return line at the reservoir, for some reason that I now forget (flushing PS?). The hose had basically cooked itself on there. Very brittle, yet still strong, and seemed like it was glued on. I ended up having to destroy the hose to remove it. But yours might be easy to R+R. You never know. Good luck. Ed

Hi torreto, not going to be easy. Looking at my 1991 LS400 shop manual (I assume this works for yours too), page FI-18, the fuel pump is inside the fuel tank. Steps to remove: 1. disconnect battery 2. drain fuel from tank 3. remove front luggage compartment cover 4. remove rear seat back 5. remove partition panel plug 6. remove fuel pump a - disconnect the fuel pump connector b - remove the eight bolts and remove the fuel pump set plate c - move the two clips aside and move the fuel hose toward the fuel pump bracket side d - remove the three bolts and remove the fuel pump e - remove the two clips Hope this helps. Ed

Random ideas that might help: - To quickly turn the alarm off, putting the key in the ignition and turning it on seems to work reliably - I've set the alarm off by: with the doors locked, but a window open, unlocked the door by reaching through the open window - Faulty door contact switches ("courtesy switch") can cause the alarm to go off. I forget exactly how, but it must be some way that the computer thinks the car is being broken into. You can easily test the reliability of these by watching for the door-open light coming on in your instrument panel. If flaky, I have found that partially removing the switch and cleaning with brake cleaner and a toothbrush can restore good contacts. - There may be some other electrical switch associated with unlocking the door (do you do it with the key or wireless?) that is working intermittently, causing your problem. The computer may think that the second case above is happening - the door is opening without being unlocked from outside. Questions - do you unlock with the key or the remote? Does the alarm go off when you unlock it, or when you open the door? Good luck, Ed

Sorry for any confusion. I believe the alignment to be just fine. I'm looking for ideas/tests/etc. related to a pull that is NOT caused by mis-alignment. My first guess is dragging brakes, but I'm also asking if there could be anything else that might cause a pull. It pulled to the right BEFORE the alignment as well. That made mis-alignment the initial prime suspect, but it has since been checked off the list. Again, let's consider the alignment to be perfect. Alignment is OK. So let's not talk about alignment. Wish I had named this thread something else. Something like: "LS400 pulls to right, and I know it is not an alignment problem"

More info: - car does not have TRAC - no weird noises anywhere - yesterday, I shifted into N while coasting on a straight section. No change - it still pulled slightly to the right, and seemed to slow down more than it should. Any ideas? Even comments on how much I should be able to spin the front wheel would help. Thanks, Ed

I've got a potential brake dragging problem. In this test you suggest, how much dragging is acceptable? I did the test, and when kicking down on the front of the tire, trying to spin it as much as reasonably possible, each front tire spun about 1 revolution before stopping. Would you call that dragging? OEM pads, no noticeable rotor warping. Just dragging, and it pulls to the right slightly when the brakes are not applied, after alignment. Thanks, Ed

The closest Lexus Dealership is 2 hours away ... enormous hourly rates and ending up paying gigantic OEM part fees. ... I have to do what I can. I like to work on my own cars and throwing money at a dealership for a car 17 years old doesnt help me down the line when something else goes wrong or needs fixing. Experience is a great teacher and I wouldnt trade this time learning how every part of my car works for spending thousands at a dealership. ... That's the spirit! This sounds like a really tough problem, and you already know you've replaced more than you needed to, but the learning experience is invaluable. Especially when you take the effort to get good diagnostic tools and think carefully about the problem as you are clearly doing. Hope the fuel pressure test / fuel pump replacement fixes it - that sounds promising. I have 3 degrees in mechanical engineering from the two best schools in the US (luckily, all was free), yet some of the best engineering/problem solving education I've had has been from fixing my cars. This started with my 1979 FIAT spider that I got in 1986. I owned it for 11 years, self-taught myself everything while replacing everything but the distributor and starter (I did engine rebuild, body work, etc.), and sold it for $700 more than I paid for it. A friend of a friend who is a space-station astronaut has said that despite all the education (Ph.D.) and astronaut training he has received, the most valuable skills he takes up into space have come from the many hours he spent tinkering with his single-engine airplane. So keep learning, and thanks for sharing the story. Ed

Sorry for the late reply - have not checked in a while. The GPS gauge is something I'm not familiar with. Does it actually say you have -27 miles left? The logic in saying you have 0 left before you're bone dry makes sense, but ... When you say it stopped - you mean it ran out of gas, I assume? Means the tank is empty, right? Not sure if I understand the logic on having 1.1 gallons left. The main thing I was saying is to not believe the gauge zero or the specified tank size. Running dry is the only way to know for sure. You can also figure out any biases in your GPS's estimates when doing this. Ed

1991 LS400, ~163k miles. Previously owned by my in-laws since new. Well maintained. has new lower ball joints no obvious problems with suspension I had it aligned 3 times in the last year, with the final one being very thorough - so I actually believe that the pull is not due to alignment. The mechanic agreed that the pull was still there. I have swapped tires left-to-right and front-to-back with little effect. Thinking that it might be dragging brakes, I jacked up the front and spun both front wheels with my foot. Both left and right spun about one full revolution after kicking down on the front of the tire (about as hard as I reasonably can). Does one rev seem to be too little? I know my Porsche will spin for several rev's. Still, since both sides are about the same, it seems not to explain the right-hand pull. How much dragging should I expect for the front wheels? Any other tests I could do to quantify this? In general, I think the car does not coast as well as I'd like it to. Any other ideas, comments, or recommended tests? Thanks, Ed

I have a 91LS with ~160k miles and replaced all 3 mounts in March. Made a huge improvement - the car felt like new afterwards. The prices you listed earlier are about what I paid, after checking things out, so you're good there. The transmission mount is a very easy job as compared with the engine mounts. If you want to try something easier as a first step, I'd say replace that. All you need is a torque wrench. Nothing tricky at all with that job. The engine mounts are significantly more challenging. By the time you get to the mounts, you may as well replace them. At your mileage, you are due. I followed Glenmore's writeup, plus the other follow-ons (I researched this a lot before diving in), and had great success doing that, along with the following modifications to the procedure (which all made it a lot easier, and perhaps less intimidating): I used a pivoting socket wrench (where the ratcheting head can pivot with respect to the handle) with a standard depth 17mm socket on it to get the upper nuts on the mounts. No problems. Passenger side first - used craftsman 17mm open end wrench with big long second wrench to add leverage when breaking it free. Came easily. On driver side, the pivoting socket wrench was essential. I removed the wiring harness + PS line as instructed, but none of the other stuff (did not touch AC, no PS return hose hold down). I just jacked the engine carefully, checking for stress buildup as I went. I did remove the air cleaner, etc. since that seemed to be getting stressed as I lifted the engine carefully. Removed both wheels and splash pan cover for clearance. I removed the oil filter (and did an oil change), but that may have not been necessary. Lowered crossmember nuts until only about 2-3 threads were engaged. I did the job 5 months ago, but took these notes for myself back then - am planning on having the car for a few hundred thousand more miles. This was all done solo, in my driveway, on jackstands, at night, in a driving rainstorm (kidding about that last one). It took a couple of hours and the driving feel improvement afterwards made it a very satisfying effort.

You never know your limits until you push past them. This applies to gas tanks as well as many other things. I joke with my friends when they tell me how big their gas tank is and then I ask them if they've ever run out of gas (and if not, then how do they really know they don't have a 50 gallon tank). Not for everyone, but if you really want to find out ... I have a 91 LS400. Shortly after getting it, carrying a gas can in the trunk, driving gently around town, I let it run dry. Some info from this: - when running dry, it will stumble, then maybe die, but can then be restarted and driven for a short distance, repeating this at least a few times. I probably got over a mile after the first stumble. - the manual says the capacity is 22.5 gallons - when filling it, I put in 21.3 gallons (accounting for the gas can and stopping when the gas pump clicked off) - During the final 2.5 gallons of fuel in the tank, the gas gauge did not move AT ALL. When the last corner of the middle line of the "E" on the gauge turns from a small triangle into a dot, it has pegged and will not move further. Of course different models/years are likely to be different, but some features of this may apply everywhere (e.g., the manual mis-stating the capacity and the gauge pegging on the low side with significant gas left). Oldskewel

I have a 91, and after getting it, I did a couple of AT drain and fills, replaced the filter, etc. No problems existed, I was just trying to bring it up to good maintenance standards. When filling the AT after doing the filter change (remove pan, etc.), I filled based on the dipstick (which I've found unreliable), which I noticed meant I put in 1 qt less than I had drained out. During the subsequent test drive, I seemed to notice the exact problem you mention. It seemed definitely wrong. I then added a qt of ATF. It now drives perfectly, and the dipstick indicates that it is overfilled. I'd recommend putting some more ATF in. Of course always Type T-4. If you're cautious, just fill to the top of the dipstick line. If braver, try a little past that. Oldskewel 91 LS400, 162k miles

On a few occasions (like 3 or 4, mostly as a test), I have floored my 91 LS400 from a complete stop (in Drive). When I do this, I keep an eye on the tach, and each time I've done it I notice that the revs go past redline. As soon as they go past (maybe 200 RPM past), I instinctively let my foot off the gas, which causes the AT to shift up. I can certainly live with this behavior, but wonder if it indicates a problem with the AT or the rev limiter. Any ideas? Oldskewel 91 LS400 85 911 Cabriolet (5-speed, rev limiter works great)