Razor61

I did some work under the dash on Friday, removed all the covers, steering cowl and the heating plastic duct under the steering wheel to get to the steering tilt/telescopic mechanism to grease the rollers. There is another post about this. I put everything back together and went out in the car, set off down the road and the parking brake light was on - stopped the car and checked that the parking brakes was actually off and it was. Continued to where I needed to go - back home and removed all the covers to check if I’d disturbed anything - couldn’t see anything, wiggled wires, parking brake switch and connectors but couldn’t see anything. I back off the drive onto the road and I can’t remember if the parking brake light was on or off when I reversed off the drive, only noticed it when I started diving down the road. Went back and forth checking things etc a few times but couldn’t find anything, dodging the rain of course. So today I remembered a post about a failed stop light causing the parking brake light to stay on, I got the Mrs to press the brake pedal while I checked at the back…….no brake lights left or right at all but the centre high level brake light works. Maybe a fuse so off with the under dash cover and checked the fuses which are ok, checked the connectors to the fuse/connector block and they look ok. Weather is atrocious so can’t start checking voltages to things or removing the rear lights or checking the brake failure module in the boot in this weather so I’m stuck without brake lights. Has anyone any ideas about this by any chance? I’ve disconnected the battery and will leave it off for a while in the vain hope that it clears the issue.

Well it’s not tyres, put the DHP wheels and tyres on - went for a run - still the same. Back home and a 30 min pit stop to put the original wheels back on, not Formula 1 speed of a pit stop but not bad for my age😀 Back to the rear shocks, maybe it is the rear KYB shocks causing the issue or maybe a broken spring, I’ll check the springs when the weather clears again. If I don’t have a broken spring I’ll order a pair of OEM rear shocks from Amayama.

Definitely better with tyres at 30psi but the correct pressure is 35psi according to the manual. I replaced the rear shocks in April, done a lot miles since then with tyres at 30psi and not noticed any slight bounciness on motorways or cr@p roads. Few weeks ago I increased the pressure to what it should be at 35psi, car felt better but noticed the slight bounciness on less than decent roads and motorways. I started to noticed it on Weds last week travelling south down the M1 between the M62/M1 Junction and M1 Junction 36, very specific because I look after a site near Sheffield so visit regularly, this is what prompted all this. Don’t remember it on the M62 before joining the M1. Been down the same M1 stretch since replacing the rear shocks in April but running the tyres at 30psi and I don’t remember anything about bounciness at all. What to make of all this………. 35psi in the tyres does make a difference and creates the slight bounciness on less than half decent roads and motorways. Reducing the pressure to 30psi more or less eliminates it. So do I run on 30psi or 35psi or in the middle at 32/33. I don’t think it’s the KYB shocks, the weight of the car is on the struts so can’t see how the shocks can oscillate in that way but it’s possible I suppose. Checked all the suspension bolts this morning to see if anything was loose, everything tight as it should be. All the suspension arms/bushes/mounts have been replaced in the last year, apart from the rear UCA’s, so it’s all tight and solid. After all the checking and thinking about it, I would guess at the tyres causing it. Not that there is anything wrong with the tyres, I went for the quietest tyres and maybe they don’t suit the car. This has just popped into my head………..the car had a set of DHP wheels on when I bought it and I still have them, I now have the original wheels on the car. If the weather clears up I’ll refit the DHP wheels and tyres and run it to work for a while. That may clear a few things up, I should have thought about this before🙄

Just remembered a few weeks ago or maybe longer, I can’t remember exactly, I inflated the tyres to 35 psi from 30 psi, which I ran from when I bought the car. It was maybe when I installed the rebuilt ECU, I remember looking in the user manual for the tyre pressure and it said 35 psi but maybe I misread it. The mk3 I had, I ran at 30 psi which is why I ran this one at the same tyre pressure. So when I remembered this I went straight out and deflated the tyres to 30 psi all round. I had inflated the tyres using a compressor and tonight I used a digital gauge. The tyres were 36 psi it turned out. I was a tyre fitter in the early 80’s so should know better, from what I remember the higher the aspect ratio the lower the pressure - the lower the aspect ratio the higher the pressure. I’ll find out tomorrow if lowering the pressure has put things back to ‘normal’.

Their tape cassette decks cost a pretty penny back in the day when HiFi was in its prime, £1000 iirc for the 1000 series cassette tape deck and it was the last word in cassette tape decks. There are various used ones for sale…………few hundred quid up to a few thousand quid. It was quality stuff back then, along with other makes that probably now only exist as brand names.

Good shout but the rear drop links and bushes have been done, in fact everything has been done apart from the rear UCA’s so the suspension is solid and tight. Maybe it needs 20,000 miles loosen up a bit………..I think I’m being too picky and sensitive about it so will see how it goes.

Thanks Pete, I didn't notice anything after I replaced the front shocks last year at all, that I remember, and I clocked up a lot of miles since then. I didn't replaced the rear shocks at the same time because I read they were a pain to change but a few months ago I found the 'trick' for doing them so cracked on and did them. Didn't notice anything apart from the wallowing had gone cos the existing shocks were shot. In the last couple of weeks I've noticed the car seems slightly 'bouncy' with anything other than decent road surfaces. Not really really bad by any means but I can feel it through the seat slightly which normally points to the rear. Difficult to explain but undulations on less than decent roads cause the slight 'bouncy' thing and I don't remember feeling it until the last few weeks. Cornering and handling are totally fine so maybe I'm just being paranoid and it's just the roads are generally cr@p. Thanks for your thoughts, I don't think it's because the rear shocks are not OEM from Lexus. Bouncy suspension normally means the shocks/dampers aren't doing much. I was just wondering what the 'odd' symptoms were. I suppose the only way to make sure is to put OEM shocks on the rear and see if it changes, it will cost me £215 delivered from Amayama plus any taxes to find out🙂

Hi Pete, do you know what the symptoms were for the 'really odd ride'?

That's cheap for both front lower arms, LPD has them listed at £316 each - highlighted in yellow below - that's if that is the correct part/s you have ordered for the triangle thingy. Front lower arm rear bushes part number 48655-50012 are £178 each from LPD - highlighted in red below - and £85 for 2 bushes including delivery from Amayama in Japan.

Went for a decent run, 70 miles round trip, mostly motorway, and I can now say something about the MPG. 70mph on the M55 motorway and the average was a very steady 36 mpg, which is pretty good. After this trip the mpg going to work and back has improved, around 26/27 mpg which is better than before and was a big surprise. To begin with, MPG to work and back wasn't much different and was down to 20/21 mpg. Not easy to quantify this sort of thing but I'm sure MPG is generally improved. After installing the rebuilt ECU it has taken a while for things to settle down and the ECU to do it's learning thing. Idle speed was too high to start with but is now back to normal. I am guessing (educated guessing) that now the ECU has settled down and done it's learning, this has improved the MPG. I was told that MPG should improve significantly, I was sceptical to be honest but seems like it has.

After a week or so driving to work and back I’m sure the rebuilt ECU has made a difference, not as much as the ‘spare’ ECU made but a definite improvement over that. Lower end torque is better for sure, not easy to describe but you can ‘feel’ it when driving. Another thing is the cruise control is better, it doesn’t fluctuate as much and is more stable. Probably due to the lower end torque improvement. Gear changes seem better but I can’t swear to it. I can’t say anything about MPG yet until I go for a decent run, it’s about the same going to work and back though.

Hi Oli, interest noted and will have a think about it👍 Good luck in your search, members will be more than happy to give their opinion on any potential purchases. There are a few decent looking LS400's for sale at the moment, emphasizing decent 'looking' cars - reality may be very different. Gold 96 in Sutton and White 98 in Middlesbrough on Autotrader White 96 in Glasgow and Silver 98 in Chichester on ebay, the white one has stuff in the MOT history which would concern me though. There are others on eBay and Autotrader which have been for sale on and off for quite a long while.

This one looks decent, not a mk4 but it looks very good. Registration number not visible or in the advert which would put me off a bit but it's a case of asking the seller for it. https://www.autotrader.co.uk/car-details/202306299063054?advertising-location=at_cars&atmobcid=soc5&fromsra&include-delivery-option=on&make=Lexus&model=LS 400

Thank you Stan, the picture was not long after I'd detailed the paintwork (clay bar, machine polishing/buffing, 3 coats of wax etc) so it looks the best it can. The car needs the clay bar treatment again this year because of tree sap and other stuff on the paintwork but it still looks very good. I've gone off the idea of selling it now, sensible side of my brain kicked in🙃 But.........................as I've said before, if someone offers me £10k I would take it. Extremely unlikely I know but you have to decide on a price just in case🤣

Carriage to send it the USA was £46, cost for the ECU rebuild was £400 + £48 carriage from the USA back to me. Total was £494 in total for my ECU, price for a rebuild is dependent on if and how much remedial repair work needs to be done i.e pcb repairs due to leaking caps and corrosion.

Just thought, I forgot the car was still warm and it fires up straightaway anyway when warm so that's no different. A couple of cranks this morning when cold so that hasn't changed. Was there any difference driving 10 miles to work? I believe there is a difference and feels even more responsive, it feels quicker and I don't have to press the accelerator pedal down as much. But it's early days and this may be all in my head...............the more I drive the car the more I'll be able to tell plus it will take time for the ECU to adjust correctly. This is a definite though: Swopped the original ECU for the 'spare' ECU - 100% sure the car performed significantly better. I can only assume the 'spare' ECU capacitors etc were more efficient and in better condition than in the original ECU in the car. Time will tell if the rebuilt original ECU has improved things again, I think it has but as said above I need more time driving the car to make a judgment. Initial impressions are good though. You never know, the car may be able to get near the quoted performance spec of 0-60mph in 6.3 seconds, which is pretty quick for a big car and pretty quick by any standard tbh. When everything has settled down I'll find out🙂

ECU update…… Received the rebuilt ECU back from Bill in the USA, very professional service and shipped back to me without any hassle and packaged excellently. Fitted it to the car after work today, connected the battery and left the ignition on for a few mins before starting, as instructed. Put the key in and turned, car fired up immediately and I mean immediately with no cranking. Good sign that it was worth doing. Tomorrow will be interesting going to work and I will be able to give more info on what difference/s it has made to the car. Main thing is it works and the caps have been replaced to prevent any issues in the future. I now have a spare good ECU, proven in my car for the past 5-6 weeks, with a master key and an uncut blade. It is for sale now if anyone is interested in doing what I have done. I’ll update this thread again tomorrow after work or maybe when I get to work, tempted to go for a drive now but it can wait until tomorrow.

The bottom 2 rollers are held in place with a very large grub screw and is locked in place with a large locking nut/ring. Flat roller contacts the steering shaft, 3 concave washers ( concave side up towards the steering shaft and roller assy) then the large grub screw and locking nut. I used a paint pen to mark where the grub screw is, removed everything, cleaned with brake cleaner, greased the roller assy, applied grease to the steering shaft through the vacant hole then reassembled both rollers. Of course it’s easy out of the car but I’m pretty sure I can do the same thing on the car no problem, I know now how it all works and what bits to remove and reassemble. spanner used was a 32mm, I think it’s a 31mm nut but 32mm did the job.

Ok, received the steering mechanism today and had a good look at how it all works. First thing the tilt plastic gear is in perfect condition, I think the worn plastic gear is caused by owners using the steering wheel to lever themselves out the car while the steering mechanism is returning to its default position. This puts a lot of pressure/strain on the tilt plastic gear and therefore wears the plastic teeth. Better to wait until the steering mechanism has stopped before getting out of the car, which is what I do. The telescopic part is held in place by 3 rollers, 2 flat rollers on the bottom and 1 ‘bobbin’ type roller on the top. Top roller: This roller is held in place by a roller ‘carrier’ with a pin through the carrier and roller. I knocked out the pin and removed the roller carrier and bobbin style roller. Cleaned the roller , used some scotch bright pad to remove slight corrosion on the roller, applied some moly grease to the steering shaft through the vacant hole, applied the same grease to the roller etc.

Oil and filter change on the IS250, washed, polished and then sorted out the oxidised headlights again with DuxBack (lasts 12 months or so) then washed the LS400. Both cars rinsed with pure water (same as window cleaners use) and when the water dries it doesn’t leave any spotting on the paintwork or glass. Took 5 hours, now time for a beer and watch some Ashes Cricket😀

Ah yes, the steel washer fix for the tilt mech plastic gear..........same setup for the mk4 or series 2a as well up to 08.1998. The same main assy was used on the LS400 for production dates 10.1994 - 08.1998 - the tilt motor part number changed but looks the same. 08.1998 on uses a different type of mechanism. My 1998 mk4 or series 2a with production date of 01.10.1997 has the same tilt motor mechanism as the mk3 or series 2 using a worm drive with the plastic gear. I'll look into the plastic gear thing when I get the used assy. I'll maybe investigate making a new plastic gear, just out of interest.

The telescopic and tilt mechanism on my 98 LS400 has been bugging me cos it’s noisier than I think it should be. Some cars I looked at had a quiet mechanism. Sounds like the telescopic motor is struggling for some reason but it all works ok. So last week I decided to have a good look at how it all works, my car has a different mechanism to the 99/2000 LS400. The 99/2000 is very similar to the LS430. If you look on the EPC website you can see the difference. So last Wednesday evening I removed the covers around the steering wheel to see if I could see and then get to the sliding tube for the telescopic bit and the gear assy for the tilt bit (which is a proper piece of kit and engineering, it’s impressive) I could get to both of them and applied some grease using a syringe, worked the mechanism’s up and down to get the grease moving around. It made a bit of a difference but nothing drastic. I suspect the guides mentioned below need some attention. The telescopic bit has 2 spring loaded guides underneath to keep the tension and stop it moving around but has to be torqued to 8nm iirc so it’s not too tight. I have the workshop manual to adjust it all etc but didn’t fancy doing it at the time and it’s a journey into the unknown plus I was going on holiday Thurs until Monday in the wife’s IS250. I thought I’d set the interior light to ‘door’ on the car but turns out it was ‘on’ so came back to a totally flat battery when I went to the car Tuesday morning, rookie mistake but a good charge all day Tuesday and overnight fixed it. Over the weekend the thought crossed my mind to buy a second hand assy, have a good look and work out what I need to do to make it quieter without experimenting on the car. Of course if the price is low enough. This morning I found the correct assy complete with all the motors on eBay and promptly bought it for £45 delivered, result. When it arrives I’ll have a good look and work out what I need to remove, clean and grease to hopefully make the assy on my car quieter and smoother. I’ll take pictures and document anything I figure out and post it here which may be helpful to someone.

Pic of the car from last year with DHP alloys.

Might be a surprise but I am thinking of selling my 1998 LS400. Most people will know what the car is like and the work that has been done. I would hazard to say that it might be the best mechanically and the best driving mk4 or series 2a LS400 in the UK, in my opinion of course😉 The car is not ‘perfect’ on the body but I would say it’s excellent condition and you would struggle to find a better combination of body/mechanical /driving/suspension/electronic/electrical condition in the UK. That is before I receive and fit the rebuilt ECU. So why am I thinking about selling? Answer is that I fancy changing to an ISF (first choice), SC430, a good LS430 maybe or maybe a GSF. Thought about a LS460 or LS600H but the suspension replacement costs are ridiculous even when buying from Amayama. I know I will never get a price that covers what I have spent on the car, I am realistic, but I think £6k - £7k is maybe achievable? What do you guys think? I’m not hell bent on selling at all but if someone on here appreciates the car, what has been done and knows that it’s good for 100k at least with correct maintenance then I would be willing to have a conversation.