Banshee365

What is your experience level with auto transmissions? Check out my thread on CL: http://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/847895-banshee365-s-95-97-transmission-overhaul.html

90179-10174 & 90177-12002

Get the car mostly warmed up, shut it down, unplug the ECT sensor the see how it runs with it unplugged. Remember there are 2 ECT sensors. One for the ECM and one for the cluster. Make sure you're dealing with the one for the ECM.

I don't know about the Gen1's but the Gen2's like to clog the strainer. The trans has a metal mesh strainer instead of a traditional paper filter. When the strainer is clogged you may as well empty the fluid out. It sounds like a low power steering system with the moaning that it does when this happens. You can remove the filter and clean it. I've battled this before where the trans was shedding material and clogging the strainer. I replaced the trans with a junkyard one but I think there was still some material in the radiator. The new trans' strainer clogged within 700 miles and it was dead again. I cleaned the strainer and installed a 3/8" Magnefine in-line filter on the trans cooler return line and that seems to have fixed that issue for me. I'll be changing that filter every year or so from now on, or maybe more often. Who knows.

What brand belt kit will your shop install? I recommend the Aisin kit from RockAuto for about $175. I just installed one on my '96 and the quality is outstanding. It includes the timing belt, idler, tencipher pulley, water pump, and hydraulic tensioner. Best deal out here right now. Aisin is what you'll get in the toyota boxes without the high price.

*118K sorry

Keep running it with the wrong ATF and 188k will be like 1 million miles to that transmission. You MUST run Type IV fluid, at least change that for now. My money is that it is ECM related sorry to say. Other than that maybe torque converter? Assuming the transmission operates normally at other speeds.

That person saying that LS's are known for ECM problems is good for his business. I don't think your model year LS had many ECM problems. Most ECM problems are with the 95-97 cars. I have a 96 and have, myself, experienced a failed ECM and BOY is it hard to diagnose. Not saying that your ECM isn't bad but keep your eyes open. It would be great for you to find someone local with your same year car to swap ECM's with just to troubleshoot. If your problems are very constant and can be replicated easily, swapping your ECM temporarily with a known good one from another car could be a quick and precise troubleshoot as far as the ECM is concerned.

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...

CuriousB is right on track from the first post on I think. The '96 has a fairly high failure rate for ECM's, especially at that mileage. I've had to put one in mine because the reference voltage in the ECT circuit in the ECM was way off causing the car to think it was never warming up. It would run great cold at startup then slowly get worse. The ECM kept the mixture very rich and my car was so bad that it would stall and not start unless it was cold. ECM's seem to be wear items on some of these LS's and routinely start showing symptoms at miles over 200k. It's whether you realize it or not in most cases. In a perfect world you would have a friend with another '96 where you could swap ECM's and drive a tank through it and note the difference. If you come across a good deal of a '96 ECM I would snatch it up and keep it for things like this. If you plan on keeping the car for a while that is one part I would be on the look out for. Make sure it has lower miles and is guaranteed if possible.

I'll throw out there the fact that for certain years ECM failures are somewhat common. How many miles are on your car? ECM's seem to start failing on higher mileage cars. Mine starting acting up around 200k. 96's and 97's have ECM problems. I think '94's are also common but I'm not sure about '92's. What issues is the car having? I wouldn't throw out the possibility of a bad ECM ever. The very last corrective action to most every check engine light code is to replace the ECM.

Check your manual but as long as there isn't much weight in the seat the car disables the airbag as do most higher end luxury cars. The specifics should be in the owners manual.

Tim, I know exactly what your problem is. It isn't coolant that you are leaking. You have simply sprung a leak with your headlight fluid heat exchanger buried inside your flux capacitor located next to the #2 cylinder intake runner. Dump 2 can's of radiator stop leak in your gas tank and tighten your muffler bearing then you should be good to go.

I bet you guy's have air struts.

It doesn't really matter which cable you pull. I just alway's do the negative. The light on the AC panel is just what you thought, completely normal It's just finding it's place in this world again.

I'm interested to hear what your results are after you install the new ECT sensor. Make sure to disconnect your negative battery cable for several minutes and start the adaptive learning strategy over from scratch. I've been down this road with my '96 with ECT problems. The car never thought it was warming up so it kept pouring fuel into the engine (even when warm) to the point where it would flood out and refuse to start until it cooled. My problem ended up being the ECM. Many others have had great sucess in renewing lost power and economy with a new ECT sensor.

Curious, I know it sounds crazy. The ECM was my problem and has been the problem for may others. I somewhat consider this a wear item because of information I've recieved from the man I bought my ECM from. He deals souly in used Lexus parts and sells every 94-96 ECM he get's his hands on to customers with bad ECM's and all with 200k+ miles LS400's. The sypmtoms started out very very mild and got the point where I knew something was very wrong. My car developed a rough idle so I replaced the caps, rotors, plugs, and wires. It still idled rough and I drove it for a couple of years after that. Then the symptoms got the point where it wouldn't even run unless you kept your foot on the gas. To the point that I listed in my reply above. Topic starter, I'm not saying the ECM is your problem but don't rule it out. It is the last repair procedure for most every check engine light code dealing with the engine in the fatory repair manual. Bar any squirrels or critters chewing up your wiring, I would bet on ECM problems over a harness problem almost any day of the week. You may just need the typical tune up items. If your car starts running very very badly you'll just need to hook up a scanner with live data and to the trained eye something will stick out. If you're car just seems to be "confused" remove your negative battery cable or ECM fuse and start the adaptive learning strategy from fresh. I am from Central FL. ECM's can go bad also from clogged evaporator case drain tubes causing the floor board to get wet and, in turn, some water near the ECM.

Actually, personally I consider some ECM's to be a wear item. I've been down this road with my '96. My family and I thought it was destined for the junk yard. It would start and run okay when cold but once it started to warm up it would never lean our the fuel/air mixture and it would start running terrible. Very low idle to very very high idle. At one point it would idle so low it would die, then after restart it would bounce off the fuel cut-off rpm at idle. What are you idling symptoms? I cleaned the IACV and tested it with good results. I changed the thermostat and also made sure to purge the air out of the cooling system correctly. It would still idle very very eradically. You couldn't drive it out of the driveway because it would shut off and you would never get it restarted until a few hours later when it cooled down completely. When you car is idling erratically you need to hook a scanner cabale of reading live data and watch the engine coolant temp while the car is warmed up. My car thought it was never warming up so it kept dumping fuel in. It was warming up fine and began to run so rich it would shut off and would try to run the idle high to warm it up all the time. I tested the reference voltage on the engine coolant temp circuit and it was all of the charts. This was due to some worn out parts in the ECM. I bought an ECM with 70k miles off a wrecked car and it immediatly ran like brand new, even better than new because it had weird symptoms for years until it just finally became unbearable. You'll need an exact part number ECM for your '95. The '95 LS is known for bad ECM's. You need to read the part number off of yours and compare it to the TSB regarding the upgraded ECM. You'll get the correct updated ECM part number and shouldn't have a problem finding a used one as a new one is $2K+. I paid $200 for mine.

BTW I bought my genuine Lexus evaporate car out of a car with 70k miles for $75, did your aftermarket core cost less than that?

Good luck to you and let us know how the aftermarket core works out. It's got to be EXACTLY the same in every dimension for it to slide into the evap case correctly and for the case cover to bolts back up with the ports exiting the cover in the right place. Make sure to ask the mechanic how it fit compared to factory for us.

I've been down this road guy's... If the parts are under $300 he's going all aftermarket. The cheapest OEM evap core is $450 or so. Evap core leaks are VERY common on LS400's. That and the compressor shaft seal would be the first place I looked if someone came to me with an A/C leak. The evap core on the LS isn't that hard to get to. Some on here will tell you you have to remove the entire dash to get to it and it take $700 in labor. I had a local shop quote me over $2,100 to replace the evap core and compressor with new parts after I had them diagnose it. I took their diagnosis and fixed it myself. Bought salvaged parts off of a wrecked low miles LS and they've been perfect ever since. I fixed my A/C for $200 except for the recharge I had a shop do since I don't have gauges. I had the evap core out in about 45-50 mins, havn't seen anyone else do it that fast. The factory manuals will help because they'll show you where all of the hidden nuts and bolts are. It's been a while but if i remember correctly you remove the glovebox, upper compartment, cd changer, cruise control ECU, ECM (more room with that out), blower unit, then the evap case cover, then the lines into the evap core and it slides right out. BTW I havn't heard of guy's having much luck with aftermarket evap cores. They never fit right. Hope your mechanic has done one on an LS before. When you pull your evap out of the case it'll either be covered in oil and grime and/or will light up bright green under black light if dye was installed before. Good luck!

You can't buy the screen seperate. You'll have to buy the whole $650 valve with solenoid to get it. You best bet if you want to replace it is salvage. The screens are thin and very very easy to tear when cleaning. Is only one of your bay's in the screen torn? If so do this: Remove your solenoid and look up into where it screws in. You'll see the passange where the fluid enters the area around the screen then passes through the top of the solenoid after it passes the screen. I think it is on the side of the cavity closest to the center of the rack. Screw the solenoid on the rack and tighten it down. Take a screwdriver or something a scribe a mark on the outside of the solenoid body closest to the center of the rack to show where the passagway lines up with screen. Remove the solenoid and index the tear on the screen on the exact opposite side of where the fluid passageway will meet the screen. That way, the fluid will have to go all the way around the screen and enter from the back to pass through the solenoid valve unfiltered. Most of the fluid will take the easiest path and pass through the intact part of the screen facing the passageway. Mine has 2 torn bay's and I did this with full confidence that it'll be okay like that. Way better than without a screen. Let me tell you guy's how important the screen is. I replaced my whole rack with a salvaged rack because the solenoid wasn't functioning correctly. The screen was removed at some point, probably some idiot mechanic that worked on the car before thinking he was some miracle worker while saving him time in the process. The screen is necessary and keeps the solenoid working freely. I cleaned the solenoid several times and go alot of black cunk out of it but it still never worked the same. It would work for a week or so then freeze up again. The steering would get very stiff due to the valve stuck in the wrong position. The excess pressure caused a few leaks in the rack so I just replaced the whole thing from a low mileage salvage. Works awesome now, nice and easy steering. That screen is necessary for longevity. My car worked for several years without it but it finally died. Index your tears away from the passageway where the fluid enters that cavity and that will be your best bet for reusing that screen. Be careful with the other bay's.

I wouldn't let it go long andre. Running oil smoke through your cats isn't that great for them. Cat's are way more expensive than plugging the ACV.

I wouldn't bother swapping a different year ECM in. I've heard similar year ECM's will work with similar year cars but you may have a CEL. Do you know someone who has a '93 LS that you can swap the ECM for a miles to troubleshoot? Not to hijack the thread, I would clean the throttle body first if you have not already. Does your car hesitate when you rev off of idle? Do you have a CEL now, maybe a bad o2 sensor causing rich run condition. Also think about your ECT sensor for the ECM. If you car doesn't think it is warming up it will run rich, but that usually has a high idle associated with it.

Most likely your A/C leak is the compressor front seal or evaporator core. I had both and replaced both and now I'm good to go. The evaporator core leak is little hard to detect so alot of times smaller shops cannot find it. The shop that ended up diagnosing mine evacuated the system, pressurized it to operating pressures with nitrogen, then shot a quick burst of 134a into it with a refrigerent sniffer and it detected refrigerent through the vents. That mean's the leak is in the evaporator case. The evaporator core is a typical leak point in LS400's. Don't let an A/C shop rip you off on the repair. I had my evaporator core out in 45 minutes. Althought I havn't seen anyone do it faster, it does NOT require removing the entire dash, air bags, etc... Just the glove box and blower.