MiLexus

I checked the belt alignment. looks good. So no morans putting the belt back in the wrong way. Ignition should not be the problem. Misfire cause nothing but unburned fuel to clean the combustion chamber. (as far as I know) The problem can not be the ignition as the rotors are dooing 2 sparks of each bank. If it was the ignition I would have had 2 black and 2 clean sparks in every bank. This is not the case. the complete right bank is dirty and black. The left one is clean. Can it be the EGR pipe or valve? or maybe the ECU that is opening the egr valve too often? this can also explain why the inlets are so black and dirty. If the EGR valve is causing this.. Why it it only one side? The EGR valve opening is in the chamber of the inlets of both banks right? Normally Black sparks point out the car is running too rich. Again I wonder: Why only one bank???? How can one bank run too rich and the other OK? How does the ECU calculate the amount of fuel that should be sprayed in?? Can it be the heads are different? Maybe someone put a different older or newer head on one bank?? Should in that case the inlet be fitting the right way? WhyWhyWhy! Maybe it's just something simple that is causing this. i have too many theories. Is there anyone who has some other theory just let me know! Thanx for the input. Cheers.

True. Garages are f***ers. They charge €300 for just one tranny at the lexus dealer here in Holland. I found them on the internet for $23 each!!! So first they ask silly prices and then they charge labour and at the end you sometimes are stuck with the same problems but then $1000 less in your pocket.That's why I prefer to do everything my self. All my cars never see a garage. only for MOT. I also have a TVR. Never took that to a garage too. Its probably the only reliable TVR in Holland becourse of that ;-) But Hey! This topic was started to help the pour guy with is transmission problems. So anyone have simmilar experience as the topic starter and a good solution for him?? I really like to hear if this was the thing or not. Cheers!

Black sparks on only one cillinder bank? What can cause this? the sparks on the other side look great. can it be some moran put the timing belt in and missed one or two tooths? or can it be the oxigen sensors on only one side are gone? Lately the car has some very strange cold start problems. When cold it stutters and I hear some small explosions when I push the pedal down. Its not revving up then. can this be related?? When warm it feels OK but then I just miss some power. Let me know if anyone recognizes this! Thanx again! Cheers!!

Hi man! Sounds like serious trouble. Did solve it yet? Check the cable that is gooing to the gearbox from your throtle valve. There where the throthle padle cable is comming out on top of your engine you wil probably find 3 cables. One from the foot pedal. One from the cruise control and one going to the gearbox. The gearbox one is also going the same direction as the pedal cable. The plastic black isolation of this cable can come loose out of his metal socket where the cable is adjusted. Metal little pins that are integrated in the plastic cable isolation can hang on the mount and cause the cable inside to be tensioned when the gas pedal is not down and the throtle valve is closed. The gearbox then thinks the engine is revving up and he want to transmit the power. Because the engine is not revved up and idling it will directly shut down your engine. So pull the extra isolation rubber from the gearbox cable on top of your engine. Check if the black isolation underneeth is on its place. If not put it back right in the hole. Do not forget to greese the cable as this was partly the cause of the problem. When the cable is too dry or dirty it pushes the isolation out of the socked when letting go the throtle pedal. Try this. It might work and be this simple. I have had this problem. Maybe you have the same. Then ask back your money and show them what it was. call them names and drive the LS for 1000000 more miles. Cheers!

Thanx mate! I think normally the LPG system is passive. When driving on euro 98 the complete gass system becomes inactive. So dont worry anout it now. I will try to make it run OK on normal fuel first. The misfiring is a good idea! thanx for that. It just take an hour to disconnect al the plastic crap and take a look at the sparks so I will probably do this next saturday. Is ther a way to measure the ignition cables? I also thought the LS all have a missfire sensor. Is this true? In that case it could be broken or just disconnected by the previous owner. Ill let you gus know when I checked. Please come up with more ideas!! Cheers! Milko

Hi Guys. I just purchased a 95 ls400. The pre ODB2 version. I have some trouble with it so Ill put my questions and findings here. I have some Idling problems and the car is shaking too much when idling. Just once in 2 days it suddenly shuts off the engine. It also starts to shake or stotter/vibrate when driving a constant speed between 45 MPH and 65 mph. When pulling or braking at these speeds everything is OK as well as driving speeds in a different range. Than it is just too smooth and everything feels fine. What causes this shaking or vibration at a constant speed? It does "Klunk" when Idling so I think I will change the engine mounts and Trannys as this is the solution according to some on this forum. If anyone has an other suggestion just let me know. I have some trouble finding the right information as my engine is different than the older version. I have two big throtle valves(at least they look like that but probably only one is the throttle valve.) Where for is the valve before the throttle valve? The most of the threads on this forum show an engine that has only one big valve. Also my fuel economy is just extreme. I can do only five km on one liter of fuel. It should be 11 to 12 according to the info from the dealer!! (When unplugging the MAF sensor the car fires up and immediately shuts down again. Idling is not possible without the MAF sensor. So ther is not much testing possible) What can cause this incredible fuel consumption? When I do a cold start the gearbox seems to stay in 2nd gear when pulling away. The car seems to stutter and it just has too little power in low revs to get it going normally. I must put the gear leaver in L to get some speed and even then it is slow until I come in the 2200 rpm area. Then suddenly the car pulls like crazy and seems to be a dragster. When warm the car pulls relatively normal but still a standing start is very slow. The first 15 mph just take incredibly long. A car like this should be able to burn rubber right? When warm after the first 15 mph the car feels reliable and relatively fast but the torque I get when cold over 2200rpm is really nowhere to be found. The gearbox is slow but seems to be working better than when cold. When I first checked the engine bay I noticed a lot of disconnected vacuum hoses. I tried to find an overview of the complete vacuum system but I could not find that in the internet for my type of engine. Does anyone have an overview of all vacuum connections? I now connected it using pictures I found on the internet of engine bays of different LS400s. So all this looks like serious engine management problems right? It can just be one stupid little sensor that is failing. What also is strange is that the car is registered as a '97 mod but it has no ODB2. That is why I think it is an early 95 car. Now I dont know how to get the transmission codes out of the computer as I have no OD switch. By the way. I have not even one code from the engine! So the ECU thinks everything is just fine. Still strange that he is this thirsty. When I bought the car I had a lot of loose vacuum hoses. I think I connected the most of them correctly but I am not sure as I still have a lot of trouble with my engine and idling.. I still have one open vacuum nipple. From the Idle control valve I have a rubber hose to the main air channel/inlet(this is normal). At the end of the hose ther is the plastic connection to the main air channel/inlet but ther is a small open nipple over there with no rubber hose connected. What should this be connected with? I found a picture of a similar engine where I can see the hose is gooing down directly but I can't see where it is gooing to. Does anyone have a vacuum overview for my model? Or does anyone know where this open nipple should be connected with? Let me know! The car has an LPG conversion but the info above is based purely on its regular 98 octane fuel settings. The LPG does not work properly as well but I think Ill have to make the car running normal and smooth on euro98 before I bring it to a LPG specialist. Maybe the car will run fine on LPG when it is also running fine on 98. In that case I don’t have to bring it to a specialist at all. It is quite some text but I hope people can tell me what they think I must do first. I also like to know how the gearbox gets his gear change signals and maybe anyone can tell me how to adjust the gearbox cable(if it is the gearbox cable that is connected to the throttle valve.) I’m looking forward to your responds. Cheers!