AdBlock Warning

Parts of this website do not function properly with AdBlock enabled on your device. To get the best user experience on our website, please disable Adblock for this website (domain) on your browser.


Regular Member
  • Content count

  • Joined

  • Last visited

  • Days Won


fsuguy last won the day on April 27 2016

fsuguy had the most liked content!

Community Reputation

3 Neutral

About fsuguy

  • Rank
    Advanced Club Member

Profile Information

  • Lexus Model
    1992 LS 400
  1. OK all you smarties, here is question that has me baffled - when replacing the fuel pump on these first gen LS400s, there are two options listed 1. The Denso, and 2. The Aisan (guatamala) Does anyone know what the difference is, and why? I was replacing the FP in my 1992, and not knowing any better, got the Denso from an online supplier based on their claim that it was an exact match replacement for the factory installed FP. When I got the existing FP out, however, the construction was all metal and much more robust, with a couple of shiny bands at the base. I did not see any branding marks on it, but noted that the Denso I replaced it with had the fuel feed nipple made of plastic, and generally appeared to be of cheaper quality (cost about $200) Anyway, I compared prices for both the Denso and Aisan from the Lexus dealership and the prices are very different - $250 for the Denso and $360 for the Aisan (Guatamala)!!! Can anyone on here shed any light as to why this is so? By the way, I think that I should have got the Aisan for my LS, just based on the pictures from the dealership website show the both side by side, and comparing that to the FP I took out of my tank! $360!!! Thanks for any insight p.s. For those who are wondering about the Denso - it appears to be working well, but I am concerned about its longevity, simply because of the apparent cheapness in construction.
  2. If I am following all of this correctly, all your electrical troubles began after the alternator was replaced? If that is correct, I would suspect the alternator. Have it thoroughly checked out first. I think the original LS400 alternator is rated at 100amps - remember that the LS has a lot of electrical components all greedy for power. Good luck
  3. This may be a bit late and you may have already resolved your noise issue. You may have a loose/ill-fitting weatherstrip around the top and sides of the window glass; however, if that were the case, you would hear a whistling noise that would be easily identifiable as the source of the noise. I would suggest checking your transmission mount; if it is worn, you will have some noise that would be hard to pinpoint as being due to the mount, but will blend in with other road noise. Also, if your sun-roof inside cover is open, you will have more road noise. By the way, the issue with road noise applies to all the suspension components - where ever the chassis is being subjected to road shock and the impact is not softened by the components (usually rubber/hydraulics, etc.) The two checks I suggested you should be able to do easily. If you are more technical, or have someone who is, you could check your motor mounts, and the rest of the suspension system. Good luck.
  4. This is an old thread, but it is germane, and will possibly help others with these old models. I did some investigating after my oil level light would intermittently come on at highway speeds over 70 or so, and then go off, even though the oil level was at the correct marker on the dipstick. Turns out that there are two possible reasons this may occur: 1. The oil circuit is not allowing the oil back into the oil pan fast enough to allow the sensor to give a safe reading, or 2. The sensor itself is marginal (since it works off and on). The sensor itself is a float type, and is different from Gen. I to Gen. II at least that I know of. The differences are slight enough so that they will not interchange between the two models without some level of ingenuity. Cost of new sensors are approximately $400.00 (yes, $400!!) Note that this is the oil Level sensor, and is accessible on the upper side of the transmission housing after the PS pump has been removed. Two 10mm bolts hold it in place, and even after these bolts are removed, some dexterity is required to get it out since the float arm has a couple of bends in it, and the float itself is pretty brittle and can break easily. The sensor is some sort of proximity activated switch inside a brass tube along which the float rises and falls; the float has an embedded magnet and apparently works by activating the switch as it rises and falls inside the upper oil pan. P/N for the sensor: 89491-14070. Now for the possible explanation as to why the sensor may be malfunctioning - the heat from the engine is transferred to the oil and over time, heat will eventually lower the magnet's effectiveness, or downright kill it. There is a good physics explanation for this, but I forget it. Another reason could be that gunk buildup between the float and the post on which it slides may reduce its freedom to slide up and down. A good reason to keep the oil changed periodically! Now you know, if you have read this far. Good luck and good night!!!
  5. Chances are that if the shop worked on the starter, the connector to the heater control valve was disconnected, and/or the entire assembly moved to allow room for the starter work to be done. I would look for the heater control valve - it is on the passenger side firewall on gen. 1 LS400 models - and should have the cable connected to a movable lever that regulates the water flow. It is an easily overlooked reconnect when other more major repairs are being done. Also, while you are about it, you probably should verify that all your related hose connections/clamps are tight to save yourself a lot of grief down the road; if they forgot to replace the HVC cable connection, who knows what else they did not re-check! Good Luck
  6. my $.02: Have you verified that your Throttle Position Sensor is not on its way out? This should be a pretty quick fix; also, you may be able to pick up a used IACV from a boneyard for relatively little, or alternatively rebuild your own one if you are careful (aluminium housing and surfaces can be easily damaged!) - it will require a careful disassembly and then some cleaning - biggest problem I found during disassembly was the three tiny flat-head screws almost getting stripped due to rust. There are two bearings,either or both of which may be failing, but an off-vehicle test will let you quickly determine whether the IACV is working properly or not; I have read where a simple oiling of this part resolved issues, but your situ may be different, if it is the IACV. There is a good breakdown for this part (IACV) on the Aussie site, IIRC. good luck
  7. Hi, If your coils and fuel supply are fine, and you have no acceleration, it may just possibly be the Throttle Position Sensor (TPS). Look up any posts on this and you may find some suggestions. I had a similar problem with my '92 and changing the TPS resolved it. For really good and detailed instructions, look up the lexls site. Good luck!
  8. Steve2006, Thank you for posting that bit of info about the '91-'92. Can you let us know whether the C6 Capacitor is the only one for the '91-'92 model years? My dash lights and Needle lights began blinking, then go out completely, and I want to fix them all in one shot (hate having to deal with those pesky connectors at the back!). Thanks for your help
  9. I know this thread is over three years old, and probably of little use except to a small group or enthusiasts, but it is good info and comes from an ECU expert (not me!) who knows about these things - many ECUs from around '88 through '99 often had capacitors that leaked after several years in service, and the electrolyte leaking onto the circuit boards can corrode the circuitry, causing all sorts of driveability problems. The good news is that with a little careful soldering and the correct replacement capacitors, the ECU can be restored to its original functionality, if the circuit boards are not damaged already. The key to repairing this is to use the correct capacitors - you will most likely not find the correct ones at your local RadioShack or electronics repair center, or places that you would expect to repair the ECU correctly. The following link - has all the correct capacitors and links to sources for ordering them, if you need to do the job. For my part, I had experienced diverse problems and decided to check my ECU - the caps looked good, but rather than take a chance of them leaking and toasting the boards, I id'd the ones I needed from the link (above), ordered the capacitors from the two companies that stocked these caps - Digikey and Mouser Electronics, spent an afternoon taking the old caps out and soldering in the new ones, and I am happy to say that my '92 is as smooth as silk and no longer has any of the issues I was experiencing! One note of caution, if you decided to do this yourself - follow all the cautions associated with avoiding Electronic Static Discharge (ESD) and look for a short write-up I left on that site regarding the removal of the old caps. The replacement caps total cost is less than $20, in case you wonder about that, so don't stint by trying alternatives or knock-offs!
  10. Great post, Landar... Thank you!
  11. You probably should begin eliminating things one at a time - first check to see if your coils are good; there is testing process that requires you to check the resistances between primary and secondary windings. Once you eliminate the coils as a potential source of the problem, move onto the fuel, etc., etc. By the way, you would get more helpful responses if you provided some more background information like whether you had any work done on it, whether it has been sitting idle for a while, whether you just got it, or other problems leading up to this issue, for anyone choosing to try and provide some guidance.
  12. Hi, Glad you have your wheels back, and working well. Also, thank you for posting your solution - it helps us all!!!
  13. This link shows the difference between the different year models: Also, if your alternator is the original one that came with the car, it is of a much better quality than the ones you get from discount stores - you may be better off getting it rewound if the armature is bad, or alternatively, if you are lucky and only the brushes are worn out, replace them for probably $20.00 at the most. Hope this helps
  14. I think you should take a look at your alternator plug - I may be wrong, but you won't lose any time if you do check it out before you pick up a replacment. The '92 has a round plug, and if I remember correctly, some other model years have a different shaped plug. Also, the amperage is around 100 for the '92, so keep that in mind as well. Given the work you are going to have to do to get the alternator out, I would suggest looking around online for a new OEM one and save yourself some more work later. However, one other thing to know if you are set on getting a used one - check for leaks in the power steering pump/reservoir in the car you are taking the alternator out of - this would be a strong indicator that the alternator is probably going to fail sooner or later since PS fluid has probably leaked onto the alternator and shortened it life. Hope this helps.
  15. Hi, This is not to detract from the sage advice given already by engineers and the very experienced - check those suggestions out as well; however, under the assumption that you are pretty confident about the state of your car/performance before the work done by the shop, and other things being equal, let me suggest there is a good possibility that the O2 sensors actually may have been affected since the work was on the exhaust system. The following is extracted directly from a Toyota manual on ECU performance (note the references to injector duration): Engine Duration Correcton Factors "...The second step involves duration corrections. Input sensors used for Injection duration corrections are: 1. Engine Water Temperature (THW) 2. Intake Air Temperature (THA) 3. Throttle Angle (VTA or IDL & PSW) 4. Exhaust Oxygen Content (OX) Once basic injection duration is calculated the ECU must modify the injection duration based on other changing variables. Variables considered in the correction calculations are coolant and intake air temperature, throttle position and exhaust oxygen sensor feedback (when operating in closed loop). * As engine and intake air temperatures move from cold to warm, injection duration is reduced. * As the throttle opens (IDL contact break), injection frequency is momentarily increased. * Fuel injection duration swings back and forth between longer and shorter durations to correct conditions detected by the exhaust oxygen sensor..." I have omitted info on the basic injection duration, but they are set by input to the ECU from engine RPM, Air Flow Meter, & Manifold Pressure sensors, which may not have been tampered with, but these are also worth keeping in mind while troubleshooting. Let us know how you resolved this so we will all be the better off! Good Luck, and hope this helps.