Wallybally

Hi, I am hoping someone will know what to look for or what to replace. I still love my LS400, its from 1991. It hasn't had any proper maintenance on it for 15 years when I got it, and now I am a year along, a couple of issues solved, but one thing remains. When it is warmed up, it starts misfiring. Today I had a brilliant idea, and popped the hood and started listening. Any time it misfires, i can heer a ticking sound coming from the top of the engine, somewhere around the cover where the leads are. The only thing I have not replaced yet are the rotors and caps. I did replace the plugs and leads. Did I do something wrong somewhere. Help !?! Thanks. Wally

Hi, Sorry, just to clarify, mine is a '91 LS400, with an idle up Air Control Valve on the underside of the power steering pump. Is that cleanable ? I was just thinking to disconnect the air hoses, cap them off at the top engine end, then leave the hoses for now, jus connect them together, until I have time to put the car on the hoist and take the valve out from the bottom. I already have got a replacement power steering pump in, for just in case, and it came with a fitting bolt in that ACV hole, so that should work ? Thanks. W.

Hi, Idle Air Control I did mean, yes. I suspect that it is rotten to the core, I'd best take it out. I've already got a bolt to put in there. just trying to get to the bottom of it. Thanks Wally

Thanks for your prompt response. Allright, putting the leads together now, and it shows 2,0 ohms as well. That's a bit of a fluke... Actually, that's the brandname of the thing as well. 'Fluke 11 Multimeter' It doesn't feel cheap, feels very heavy. It has a stcker on it that says 'Calibration not required' It should be working allright then ? Lol I'll see if I can find some other analog meter that is more precise. Thanks. However, the rough idle is still there. I have found some stupid things I did and with that I had created a vacuüm leak. Some 3" hose clamps were busted, so now all of that is repaired. Maybe someone could tell me what the exact function is of the ACV. I suspect that that will be the last culprit in the chain ? Thanks. Wally

Hi guys, Does anybody know when to replace the fuel pump resistor on my 1991 LS400 ? All data I can find, including the numbering on the thing itself says that it has to be 0,73 ohm, and when i measure it with my digital multimeter, the value is 1,9 - 2,0 ohm. Seems to me that when the secondary fuel pump relay (the yellow one, just above the resistor) switches to it, the fuel pump will be slower than spec. Should I replace it or just completely bypass it ? Thanks. Wally

Actually, a mechanic I know says that WD40 has the added advantage of pushing out the moisture, which was a problem 6 months ago. I could not get the key in the lock on the drivers side, it was frozen solid. I tried teflon, but that didn't work at the time. But WD40 is a electrical contact fluid as well, so the electrical connections in the lock itself seem to work better now. So when it fails again, i got the spray in the trunk. WD40 has lasted 7 months now, no issues yet. Thanks !

Just an update for anyone that is interested : After 1 year of use, the engine started to run on 7, sometimes 6 cylinders. This made me order some parts, and do some work; replaced coils - the issues were still there, running very uneven, car was still shaking. repaced wires and plugs - very interesting issue found : After removing all air intake parts, I got to the wires, took them off. Then I stuck my trusty 16 mm wrench (is that what you call it ?) in there, and was able to unscrew all plugs BY HAND !!! They were leaking very badly, none of them were clean. I replaced them, used a torque wrench for 18 nm, then put on the new cables. This was a challenge because the were a bit too long, so very fiddly work. Put everything back in place, reconnected the battery and voila ! Running very smoothly. After some investigation into the service history got me the info that the last time anything was done like this was 14 years ago. Has anybody ever heard of the plugs coming loose by itself after that amount of time ? Very strange. Other than that, I think the last mechanic may have been in a hurry and never took the time to put the torque wrench on. There never was anything wrong with the ecu, I tested it on the car. It may run a little richer than the new one, but it works. Also, The doors work fine now. Used WD40 for all the locks. W.

Hi Guys, Just wanted to let you know, I found the LCD display itself on ebay for a mere 40 bucks, had it sent to europe, did the soldering myself with the tutorial @ lexls.com, and voila : it works. Total cost about € 60,- aka 90 dollar (I think, what's the exchange rate again ?). I found the link again : http://www.ebay.com/itm/Lexus-A-C-Climate-Control-LCD-DISPLAY-SCREEN-LS400-1990-1991-1992-90-91-92-NEW-/131261754806?pt=Motors_Car_Truck_Parts_Accessories&hash=item1e8fcf6db6&vxp=mtr Is that a deal or what ? W.

Hi all, I've been searching the web and particulaly this forum for any info on the '91 Pioneer system ina my LS. An new double din radio nav-system with TMC (traffic-info) and DVB-T (Terrestrial Digital TV) are in place, and it works just fine. Connected it using a Metra wire harness for this car, but I'm having trouble getting the subwoofers going. In the boot I have the Amp on the left, two speakers in the middle (one against the rear seats and one under what we call the hat-tray) , the cd changer on the right. The cd changer I had to disconnect, because it started making noise, using battery power while the car was locked. First problem solved. The next thing was, the Subwoofer Amp was making a popping noise when I turned on the ignition. Also when turning the ignition off again. After experimenting with the radio's sub output, connecting it to the Amp through the wires behind the radio, the subs were making a lot of popping noise in sync with the music that was playing. So not working at all. But I read a very old posting somewhere on this forum that they got it to work. The question is, how ? It was working with the old original Pioneer radio. What kind of signal did that give to the Amp ? Does the Pioneer Amp have an input gain somewhere that will fix this issue ? I hope someone has some info on this. For now I have disconnected the Amp as well, so no more popping. Can someone please dig in to their memory ? Thanks. W.

Hi Adrian. Nope, temperature is not an issue, so I suspect an electrical connection somewhere being corroded. I haven't had time to deal with it, so I'm leaving it for now. I just replaced the old radio in the head-unit and have some issues to deal with there. The wiring on these cars is a very very very very tricky.... Thanks. W.

Well, I am saying that the affected door will not open when using the key in the door or using the switch in the driver's door. When that door is open, it will close by using the key in the door or the switch inside the driver's door. Only when the key is in the ignition, and the door is unlocked and open, manually locking the door (whlie the door is still open) i.e. using my finger to flick the knob to 'locked' results in a signal that opens all doors. Probably a safety system, perventing you from locking the doors manually when the key is in the ignition.... LOL Therefore, the actuator is fine, it's just a problem of a signal not reaching the door somwhere. Still with me ? ;-) W.

Ok thanks. Will be checking coming weekend. Let you know what happens. W

Just to tell you all, I've got some new information about the door lock actuator : I found something silly when I picked up a friend. We drove for a while, We got to where we were going, and then the strangest thing happened. The engine was not running, key was in the ignition in the off position, my side (driver) door was closed, he opened his door, and because he knew that I had trouble with the passengers side door locking/unlocking, he tried to lock it manually, like you would when in an old car without central locking. Here it comes : ALL the doors were getting a signal to open and all did, so the one thats is normally not opening, opened ! Repeatable. Key has to be in the ignition in off position (just stick it in). Open door, close the lock, and all will open. Even the one that normally doesn't. This assures me that this is an electronic problem that I don't know where to look for. Maybe any of you have an idea where the unit is that controls this ? Thanks. W.

Hi, Thank you all for the info. I've got three days off work, so I have some time to tackle this. I still think this is an awesome car, but you need to drive it, not let it rot away in a garage somewhere. Thanks ! W.

To answer Randall, indeed by 'opens' I mean unlocks. Operating the switch operates the lock actuators, but the one in the passenger front door will not open, it will close. I will check out the link, thanks. Sorry for the confusion. Brw the link you sent geve me an error page lol. W.

Hi, Yes, when I operate the switch on the drivers door to open all doors, only three doors will open, the front passenger side will not. When I open it manually, when I push the button to close them all, they all WILL close. So that's an electrical issue of the actuator ? Not sure where the connector is, probably inside the door somewhere, so I will have to take it all off and see where it is. Does anybody have a manual somewhere of how to take the panel off, or should I just take my trusty electrich screwdriver an screw away ? Lol Thanks. Walter Thanks.

Hi, Well, it has been maintained over the years, but it was driven very little. The one thing I know is that no ECU problems have occurred, because I think it has been swapped out already, when my stepdad got it from the dealer. Why do I think this ? Of the 3 plastic bolts underneath the kick plate only one remained, so they were in there to do stuff. I live in the Netherlands, so plenty of Toyota dealers around, that can do the timing belt next year. I thought there was trouble with the ECU because of irregular rpm at idle, but after burning two full tanks for the trip from France to here, that problem has gone away. It seems old fuel gets bad. Als, the battery terminals were replaced, and a new battery installed, so the french mechanic did a good job. I am keeping an eye on the things you said, but it runs very smooth, and the only thing I see coming is the throttle pisition sensor, which is something they can do together with the timing belt. Also, a friend of mine works at Denso, so parts I need can be arranged easily, and a new alternator and starter motor will be available when the need arises. Thanks for the info. Walter

Hi all. I've got an LS 400 1991, which I got as a gift from stepdad ! It has been sitting in a garage for 12 years, and a few things were not working, but the one thing that really bothers me is the fact that when I use the key to unlock the doors, all doors except the one on the passenger front side opens. Then if I open it manually, when I use the key on the drivers side it will close. I have dug around in the postings here, but only found referrals to the actuator. However, when I just got the car 2 months ago, the door did open, , and after a few days it just stopped doing that. Then I drove the 1390 km back to here, and it now starts to annoy me . I am thinking this is an electrical problem. On the same level - the switches for registering that te door is open both on the right side did not function properly, and I fixed that with some WD40, and now they are back to working order. Would there be a similar fix for the lock actuator ? Just spray in some WD40 and move things in and out so the electrical connection comes back ? Similar problem for the gear lever indication lights in the dash. P-light sometimes will not come on, Neutral does work, but the Drive-light stays off. Makes me think that theres a board attached to the gear stick that moves a connector, and the copper just has been oxidizing, I just don't know how to get to it so I can clean it up. Any help with these is welcome ! Thanks Wally