Banshee365

Hey guy's. I spent the $15 for the 2-day subscription to the techinfo site and downloaded all of the manuals. One problem with doing that is most of the links in each document do not lead to a file that is not in the same folder as that page is. I've got alot of problems such as high idle, running very rich, hard to start when warm, smells like rotten eggs, etc... and the Diagnostic section in the manuals points to fuel pump circuit problems as well as others. I cannot find the fuel pump relay diagnostic manual with the page (SF-54) and I also can't find (SF-53). Does anyone here have these pages? I also have a P0115 coolant temp sensor circuit malfunciton CEL code along with all of these problems, even after I installed a new sensor. I'm torn between having fuel issues, or the ECU. autoecu.com in Tennessee say's they'll check the ECU for $55 for problems in the circuits. The car runs fine when cold for the first few minutes then starts idling really high and running really rich. It idles between 1,200-2,400 rpm out of gear. It's crazy. Any ideas? I'd like to troubleshoot the fuel pump relay and make sure the fuel system is working properly.

1: Wack the top of the dash over the gauge cluster when it sticks. 2: Take cluster apart and wipe excess lube off of the needle rest with a q-tip.

Is the procedure pretty close to the same for a 96 model Evaporator? The factory manual says to remove both front seates, side interior trim, steering wheel and both airbags, entire dash and dash support to get it all out. Is it possible to remove the evaporator due to a leak by just removing the passanger side airbag, glovebox, etc...?

On page 1 there is a thread linking to another great thread on this issue. You'll either need a new ECM with the correct updated part number or send yours off to be re-flashed. All of the info you'll need is in this link on page 1: http://us.lexusownersclub.com/forums/index...showtopic=55844

Just got back inside after working on the car. There havn't been any replies but there are some views so I'm guessing some poeple are curious as to what comes of this issue. I know that alot of my posts are problems but I'm just trying to start subjects and have several educated opinions on the issue and just try and add to this great resource for others to find under the search function. Even if you don't know what the issue is any post is better than none if it can raise other questions and possibly help each other come to a conclusion. Alot of these issues are common but sometimes have different techniques and possibilities to solve. Anyway's, no to my steering issue. The steering rack was replaced by a shop in town after another shop that serviced the car flushed the power steering with power steering fluid. The whole system took a crap and I know for sure that they replaced the rack but not too sure about the pump. They may have just replaced the seals or something. I HIGHLY doubt they replaced the rack with an OEM part, probably aftermarket. I removed the solenoid on the rack today with channel lock pliers after unplugging the connector and unclipping it from the bracket. I had an oil pan ready to catch the 1/2 qt or so of mercon that drains out. Try and keep the draining fluid out of the connector obviously. After pulling it I find that there is NO screen around the holes on the solenoid. The aftermartket rack must have came with the pressure regulating valve w/ solenoid because they shop used crimp connectors to splice the connector on to the new rack. I thought the climp splices were some of the problem with extra resistance to the solenoid. I measured the resistance on the solenoid between the connector pins and then stripped the insulation past the splices and the resistance was pretty much exactly to the same. The factory manual states resistance between the connector pins should be between 6-11 ohms. Mine was around 8.5 ohms. Then connect a 12v power source to the solenoid and make sure it clicks. To make sure you know which pin is negative and positive you would be better off being able to refer to the manual. I don't really know what may happen if you hook it up backwards. Anyway's, mind did not "click". My solenoid would slowly try and move less than 1mm. It appears the valve should move down much more than 2mm. Only enough to cover the holes and block flow. I sprayed carb cleaned up inside and then some WD-40 and it sit. I then soldered the connector and got rid of those crimp connectors. Gives me more piece of mind. I then took a nail and pushed down through the top of the solenoid down on the valve. I was able to kind of break it lose and pump it up and down without electrical power applied. The WD40 started to break some of the stuff up. I poured the WD40 that was inside out and it was pure dark black. I cleaned it out and sprayed some more WD40 inside and pumped the valve up and down and it came out black again. After this the solenoid had more of a "click" to it. I reinstalled the solenoid and hooked it all back up. The resevoir took about 1/2 or so, not exactly sure, then jack up the car so the front wheels are off the ground. Turn the wheel back and forth lock to lock several times, with the engine off. Then check the fluid again. Put the car on the ground, started it up, and drove around the yard holding the steering at left and right lock for 30 seconds several times. After driving the car after all of this it steered soo much better. Before it wouldn't return to center as it should, you had to manually steer it back to center. Now it steers much much much easier at all speeds, especially near idle. Here is a question for you after my experience tonight. The car used to not only be hard to steer but it had a "ratchet" type of feel to it. As the wheel turned it felt tight-lose-tight-lose-tight-lose then lock. This happened slightly more to the right than the left. What was weird was that you also feel it turning the wheels while they're off hte ground with the engine off. No pump or anything is involved then. After working on the solenoid the car steered much easier but still had a little of that lose-tight-lose-tight feel. I'm pretty sure the rack is aftermarket and my mother (it's her car) drove it into a hole in the yard pretty hard. I'm thinking this may have warped the rack somewhere. It may just have been built and installed that way since the rack is aftermarket. I'm pretty sure it's just a quality issue with the current rack than anything else since you can feel it with the engine off and wheels off the ground. Would you guy's agree with that? It just has a little catch every half turn of the wheel or so. Not a big deal to me as long as it's easier to steer and doesn't leak etc... Here is what I feel may have happened. As I mentioned, the solenoid did not have a screen. It should... I think some grit, dirt, metal shavings, etc... got down into the solenoid and kind of got it stuck. The carb cleaner and WD40 and pumping with the nail seemed to clean alot out. Not it works more as it should. The factory manual doesn't really point towards the solenoid screen with hard to steer and poor return to center. It just points to the PPS (Progressive Power Steering) system. I definetly think this screen should be part of somewhat regular maintenance and first looked at for any power steering feel issues. It also allows you to add some new fluid. Mine was still nice and red so I didn't flush the whole system this time. Those of you with black fluid should consider flushing with the return line disconnected. Any comments or suggetsions? -Kelly

My '96 LS is returning to center very poorly and is hard to turn at lower rpm's. Hard to tell at highway speeds but it feels like there is more power to the rack at higher speeds. I've got the factory manual and followed the test procedure for the PPS system. The resistance on the solenoid is within spec but when I put straight 12v power to it the plunger inside moves maybe 1mm tops down and does not make a clicking sound. Would this cause the steering to feel very hard at lower rpms? There is also no screen on the solenoid around the holes. That was odd to me. The rack was replaced after a shop used power steering fluid in the system and it ate the seals up and started leaking like crazy everywhere. Has anyone tested their solenoid and does it actually click or should it only move 1mm or so slowly. Seems like mine is faulty but Lexus wants $580 for a whole pressure control valve w/ solenoid. Think I might go to a junkyard for this one. Any ideas?

Hate to bring up this old thread but it's the same issue I'm having. I figured I may as well post here instead of making a new thread on a duplicate subject. 1996 LS with P0115. Car has been acting really weird lately with super low idle and stalling. It's hard to start back up after it stalls. For the past few day's it's been running normal again for whatever reason but I've got the P0115 code. I JUST replaced the coolant temp sensor for the ECU under the plug wire bundle. The code went away for a while but is back now. I'm planning to download the manuals today but I'd like to get an insight I could on this issue. With a new sensor what else could it be? The gauge on works like it should and shows nothing abormal. Should I replace the switch too? Could a, what appears to be working fine, temp switch cause this light? Maybe I'll test the resistance one the car cools down. It'll be tought to get it to 70 F with a 95 F heat outside!

I drove the car around some tonight and the idle never really went much below 600. I did slightly adjust the TPS as I had adjusted it before due to a high idle which I think was caused by a bad coolant temp sensor. I don't think the car ever thought it warmed up so the idle stayed high. I replaced that and the idle still stayed fine after the TPS adjustment. I thought that may be giving me some low idle issues after I replaced the temp sensor. I adjust it up and after starting it and letting it run for a few minutes, after it's already warmed up, the idle was around 900. It was definetly too high because it would slam into gear. I tweaked it down just a little and now it sits around 650 in gear and maybe just slightly higher out of gear. The car seems to have a different logic while it's in gear that keeps it at 650 it the TPS is remotely close to where it should be. But when you take it out of gear it seems like it's depending more on the TPS. Even when the idle was 900 out of gear, after it would slam into gear it settled at 650. I also noticed the car decellerating much slower than it should when the idle was high. After the adjustment it felt more normal. As of tonight the car is running okay and the shuttering upon reving out of gear doesn't happen. That only seems to happen when it starts idling low and tries to quit. It's like it richens up and starts running like crap, didn't know if that was the limp mode. I feel I can somewhat rule out the ECU because if it dies it seems to be from too low of an idle and too much fuel. It doesn't crank right back up after a key reset like most ECU related idle problems do. If something is wrong with the car I wish it would just stay broke and quit playing games with me. If it stayed like it ran this afternoon and tonight it's perfectly fine. But the fact that it could start acting up again worries me. If it quits in traffic like that it's VERY hard to get started and almost acts flooded out and you have to wait a while before it will crank back up. I hate cranking on this car because I don't want the starter contacts to get hot and have to tear it all down for that as well you know? As far as a code reader. I usually just goto Advanced or AutoZone and get it read for free. As I mentioned before, the current code states an issue with the coolant temp circuit. I want to figure out how to clear that code. The temp sensor is new but the code remains. I'm planning to spend the $10 for a day to download the manuals and maybe it will have some troubleshooting procedures for that particular code to help me out. What do you think? Thanks for the help!

The ECU is not a rebuildable item as it is solid state. It is only programable/flashable with the right equipment. I'm afraid, if that diagnosis is correct, that you have to replace the part. The good news is that it is generally easy to replace compared to many other jobs that the LS requires during it's life. Toyota estimates the job to take .8 hours or 48 minutes. We need more info on your car. Shall we guess that it is either a '95 or '96? Does the car start back up after it dies from a stop and idles fine after that or does it still idle bad after the shutdown? Does it alway's shut down at a stop or only after highway driving? Give us some more details. But to answer your questions directly. No, you cannot "Rebuild" your ECU.

I do not have a way to check ECU codes. Is that the port under the hood or just the one under the dash? The current CEL problem indicates an issue in the coolant temp circuit. I've replaced the temp sensor but that didn't seem to do anything. Not near as much as I've heard people on the LOC that feel like a new car after they replace their sensor. On my diesel truck you can hook up a diagnostic computer to it at the dealer and read what every single parameter is doing. You can actually see the position of any valve or selenoid. Is that possible on the '96 LS? If someone could watch the activity of the IACV and other things maybe it would be easier to pinpoint. The car runs fine and revs off of idle right away for the first 10-15 minutes. Then it usually starts idling around 200-300 rpm and when you hit the gas the rev it it bogs down another 50 rpm for a second then revs up while some black smoke puffs out the back. I think the car has the original cats and o2 sensors but there are no codes for the sensors at all right now. When coming to a stop while it's working right it the idle stays around 800 while slowing to a stop and it downshifts to 1st and that keeps the rpms up as well. Other times the rpms will just roll on down to 200 then die at a stop. Yesterday it died before I even came to a stop. The car is hard to start afterwards. Unlike the common ECU issues, which seem to fire right back up after it shuts off at a stop. This car is hard to start again if it shuts off itself with the low rpms. It has to sit for a while as if it's flooded. When you finally get it started after letting it sit it's run rough and black smoke poors out for a second. I'm lost as to what it could be. If it's broke i wish it would just stay broke and now run fine then run horrible, then run fine, then horrible.

I really need help guy's. This car is primary transportation and now it's dead out in the road in front of my driveway. It starts up and runs fine for 5 minutes then starts running rough, idling low, then quits and will not restart. You can smell ton's of fuel coming out of the exhaust and it just won't crank. What the heck could be going on. I'm really starting to blame the ECU.

Got the car all apart and cleaned the IACV. It didn't move very fast but after about 10-15 passes with a negative battery lead the valve would open and close. Installed everything back in the car after cleaning the EGR modulator as well. It started up great and idled a little high while cold as it should. RPM's at idle settled down to around 650 rpm as it should. Drove the car and it ran great. The steering is still stiff but I still need to clean the screen on the rack to try and help that. The pump may need a rebuild too. Anyway.... I shut the car down and it sat for about 5 minutes. I came back outside and cranked it up again. It started idling really low again. I drive it and the first stop I come to in my neighborhood it goes down to 100-200 rpm again before dieing. It would start right back up but would still idle at 200 rpm. I got it home and it died on me again in the driveway. I tried to start it back up and it just cranked and cranked. Finally after about 10 seconds of cranking it started to sputter and a puff of black smoke came out of the exhaust. the engine then raced way up without me touching the gas. It bounced between 2k-3k for a while without me touching a thing. Doesn't seem like a IACV could open far enough to let that much air in... It idled VERY irradically and I finally just shut it off while pulling my hair out. Several hours later I go outside and it cranks up perfect and idles just great. What the heck could be going on. The current CEL shows a problem with the coolant temp circuit. I've recently replaced the coolant temp sensor for the ECU and the code went away for a while but came back. It returns immediatly after clearing it. It seems to me maybe the ECU is recieving or interpreting extreme hot then cold then hot then cold to make the revs bounce around all crazy like that. Does anyone have any ideas what's going on? Is my ECU bad? This is a tough one for me to diagnose...

How much should the valve move after each pass of grounding out the S1-S4 pins? I sat there for a few minutes and got the valve to open and close but it took longer than I thought it would. I figured it would close and open rather quickly. Any thoughts?

Hey CuriousB, thanks for the reply. That's not quite the valve that is in the 96 LS that you have pictured. This one doesn't come apart but I could try soaking it in WD40 overnight and see what happens. I'll only replace with another Denso unit because I've heard when it comes to IACV's you go OEM only because of the calibration and how it must interact with the ECU. I'll try soaking it in WD and see if I can get some action out of it. Has anyone else been able to free these things up after frozen?

Hey guy's. I tested my '96 IACV as per some factory looking instructions that were posted on this forum. http://us.lexusownersclub.com/forums/index...ost&id=7853 on page 8. While grounding S1-S4 over and over the valve doesn't move. It makes a clicking sound but doesn't move. It also doesn't move grounding from S4-S1 to open the valve. It just makes a clicking noise. I can't afford $700 for a new valve right now for this car and have tried cleaning this one with valvoline carb cleaner and a wire brush on a drill etc... It's still stuck. Looks like it's a sealed unit and it's unable to be rebuilt or taken apart. Are there any special techniques to unstick these things or do I just have to replace it? What's the best way to replace it? New or a salvage yard? I've got a call into one now and he's checking for me but the engines he has sitting around have 140k-250k miles and I don't see how the IACV could be any good unless it's been replaced recently. Any advice? Thanks! -Kelly

Hey guy's. There are several vacuum lines that have cracked all the way around where they slide over a fitting. They're old and brittle on the '96 LS. The line from the PS air valve to the front of the intake manifold is cracked. There is also a really bad line that crosses over the front of the motor from the intake tube to the drivers side of the motor that is cracked and unusable. These lines are formed to make certain corners and such. I know alot of people have had to run into this as well and I'm wandering what most do to replace them. Do you look in junk yards or just replace with straight fuel line and try to make the bends as necessary? Thanks! -Kelly

Curious, thanks for your reply. I'm going to try and clean up the IACV this evening or tomorrow morning. The tach is correct and the engine is idling super super low and it sounds like an old packerd V12 if you've heard one that idles very low. It does idle a little rough due to the low idle. I'll update as a soon as I try out the car after the IACV cleaning. I also read somewhere that it should click when the engine is turned off? Also, do I have to apply a charge to it to clean it? Thought I read that somewhere too.

Well this morning the car started after a small amount of cranking. It idles at 200 rpm in neutral and about 300 rpm in a gear. I don't think this much of a variation from what it should be is due to the adjustment of the TPS. It seems like it has to be the IACV or ECU. What do you guy's think? I still don't know what is up with the power steering. I'm going to try to clean the screen on the rack and check for vacuum leaks to try and get the steering feeling right again. It's still too stiff.

What a coincidence this thread is. My '96 LS400 is sitting in the garage dead right now. The car developed 2 symptoms at the same time, however they have both happened before and went away after a while. The car has pretty new plugs, wires, caps, rotors, and a cleaned throttle body. The car sometimes starts and the engine races to 2,000 rpm's and you have to tap the gas to get it down. Lately it's been starting normal and settling down to about 650 rpm at idle. I have also replaced the coolant temp sensor with, what seemed to me, an improved idle throughout the day of driving. It used to idle really high even when warm. The sensor seemed to fix that. The car had been starting fine and idling correct. If you drive the car, not even on the highway, and come to a stop the idle goes down to about 200 rpm and sometimes dies because of it. It usually starts back up but sometimes is hard to start. The power steering has also gotten very stiff and doesn't seem to change much with an increase in RPM's. It's like driving a manual steering car. The fluid level is fine. Right now, after experiencing those symptoms today, the car is dead in the garage and will no even start. I think it may be flooded but you can smell gas and everyone once in a while it will try and fire but just won't stay alive off of the starter. What could be wrong with my car? It's primary transportation and need to get it fixed soon. The "jerking" has never been experienced in this particular car. I'm almost positive that the ECU is probably the first generation one. Should I look into the Idle control valve on the power steering or the IACV for the engine? Trying to figure out which one I need to replace first. I don't have money to play with replacing random parts. Thanks for the help in advance and hope this thread can help some others with this issue if I can get my resolved as well. -Kelly

Thanks for the reply Python. I'll check the VAC lines. Wouldn't an EGR issue throw a code? If not, what are some way's to diagnose the EGR valve and whatever else could be causing these issues. I do not have the factory repair manuals. I've also heard about cleaning out a filter/screen on the steering rack, where is that? The power steering seems to work okay at times then out of no where will get really hard to turn. Sounds like it could be something to do with the control valve on the PS pump if it modulates the power of the pump somehow. I'm not sure how this particular system works.

1996 LS400 with 203k miles is stalling at stop lights. The CEL just came on with a reoccuring code that I thought I fixed. It say's cooling system circuit malfunciton. I've replaced the coolant temp sensor and felt it made a good difference. Several things happened at one time. The CEL came on, rev's go way high at start until you tap the gas to get it back down, and it's started stalling at lights again. Does this seem like it's still an issue with the coolant temp sensor? Maybe the contacts or something? Could the thermostat cause these symptoms. Personally, I wouldn't think so but am not sure. Also, the weirdest thing that started happening is... The power steering has gotten hard to turn, even with the car is running fine for the moment. It doesn't return to center like it usually does when you let go out of a turn. I was thinking maybe the pump is going bad and is bogging the engine down but that doesn't really explain why the revs are jumping like crazy after start. The car has recently had new plugs, wires, caps, and rotors. I really appreciated any help that can be offered, thanks!! -Kelly

Bump. Any info would be great appreciated.

Hey guy's, still need to fix my A/C. It's leaking out about every 2-3 weeks and I need to diagnose this problem and fix it. I'm kind of thinking the evaporator is leaking because the a/c shop can't find any leaks with the dye in the system. They've checked several times. Does anyone else agree that that is what it probably is. If it is, how difficult is it to remove the necesary dash components to get to the evaporator core? Is there anyone who has done this job themselves that could offer any tips. Thanks guy's. -Kelly

Check the cabin filter behind the glove compartment. If it's 100% clogged the blower will run but you will hardly feel any air coming out. -Kelly

N.E.C., I found the air supply problem to be completely a cabin filter issue. It clogged very fast from dusty conditions I guess. I had cleaned it out some a year or so ago. It blows great now but still leaks. The A/C shop tried dying the system again and still can't find a leak. It leaks out every couple of weeks so it's somewhat rapid. Where would be a good place to look or a good place to tell the tech's to look. A/C systems are a bit out of my expertise as far as DIY. I do not have the gauges and tools to fix them. Summer is coming in FL and this is a #1 priority. Where is the evaporator core located and should it be covered in a oily film or something if it is leaking? Would it be obvious? It's been leaking for a while. How hard is the core to get to? I'm afraid of anything removing dash parts because I bet with their age they will crack or break. Will Toyota work on the A/C you think in case anything breaks? Thanks!!! -Kelly