Razor61

That is a stunner right enough and 40k miles. Antenna looks knackered though so not for me, only kidding of course🤣 - it looks a cracking car. Not always good to get an older low mileage car but for an LS400, at least mechanically, I don't think it's an issue plus it has done mileage in between MOT's. Talking about low mileage LS400's, I looked at a 48k miles iirc Gold LS400 in Leeds a few weeks ago and some of you may have seen it on Autotrader for £3750 Long story short...ish. Fault where the car wouldn't run for more than 10 mins and no MOT, it was worth a look so I had a nice drive over, had a look and took my laptop with 'diags' installed to plug in. Engine running fault as above. Alternator had failed, new alternator and battery fitted then the engine running issue since. No mot, AC has a leak so not working, wheels needed refurbing, a few rusty paint chips which is to be expected, bubbling rust on the bottom of the drivers rear arch (boot end) which was a real shame. Plus points - engine was very smooth with no untoward noises when running, interior was excellent and would come up like new, gold paintwork wasn't as faded as most and very good, original electric antenna and working fine, no signs of the boot leaking.....yet. Overall pretty good, apart from the bubbling rust on the bottom of the drivers rear arch which is normally a sign of bigger issues when investigated. The bubbling rust on the bottom of the drivers rear arch put me off and I was disappointed to be honest so plugged in TeschStream and there was a 'current' Crankshaft sensor error so the running issue could have been an easy fix but it could also have been an ECU issue after the alternator issue or something else. AC could have been a leaking 'O' ring but could also be an expensive fix. MOT........who knows - I wouldn't have expected it to be bad but you never know with bushes and ball joints etc. I figured the car needed £2-£3k spending to fix get it into decent shape and fix all the issues, could also be a lot more though.

looks like someone else has had the same issue https://www.lexusownersclub.co.uk/forum/topic/127966-ls430-coolant-leak/

Forget that, just re read the original post. The floor mat isn't wet on the top so it can't be that.

Could it be the vent on the transmission tunnel spitting out water/moisture?

Couldn’t agree more, fully stamped main dealer service history isn’t ‘the holy grail’ and only shows that the recommended service has been carried out. It doesn’t mean that any issues or potential issues detected when carrying out the service have been rectified, invoices will show this.

Yep, I trust the service guys at Lexus Bolton. As for the cost, I'm not 100% sure but I think it's £175 for a full AC service - checking the AC in general - more gas if needed - replace any O rings leaking and the Anti- Bac treatment.

A very good link and explains things better than I did🙂

We have a 2010 IS250 as well which was in for its service a few weeks ago, the AC bacteria levels were measured and were very high, they recommended the AC service thing and I said I would think about it. I can’t remember the figures but it was way into the ‘red’ zone. It’s back in for its MOT in a couple of weeks so will have it done. No smells or anything in the car, if the Lexus dealer tells me the bacteria levels are very high and above the acceptable levels then I have to believe them and do something about it.

Just to clarify something, the ‘smell’ I mentioned wasn’t a bad mouldy smell. It was more of a humid taste, if that makes sense. This has now gone and the ‘old car smell’ has gone, maybe because the AC treatment has acted like a giant air freshener or it’s done it’s job fantastically well. Air conditioning does just that, conditions the air, heats when needed, cools when needed, dehumidifies when needed, controls the flow of air from outside or inside and maybe humidifies. When it dehumidifies the moisture has to go somewhere, it goes into some kind of tray then drains out under the car. So there is moisture/water in the ‘system’ and around the evap coils (I think that’s what they are called) and it drains into the tray thing. Turning the AC off stops the moisture accumulating and then the ‘normal’ air flow going over the coils etc helps dry everything, that’s how I understand it. I was told by an Automotive AC guy that when people don’t use their AC for a long while then suddenly start using it, the moisture goes into the tray thing and reacts with the dried residue and causes the smell. Also residue on the evap coils probably.

I’ve been following this and it’s a tricky problem. I’ve had the leaking boot issue on both LS400’s I’ve owned and replaced the boot seal/weather strip with an OEM replacement and no issues at all after that. For what it’s worth, in your case this is what I would do. First off I would put some Bilt Hamber Deox Gel all over the rusted areas, cover with cling film and leave for 24 hours, wipe off all the gel and repeat until all the rust has completely gone and you know exactly what good metal is left. Deox gel removes the rust and doesn’t ‘convert’ it and works really well. Once that is done and you know how much good metal is left, it can hopefully be dealt with by cutting and welding in new metal without damaging the surrounding body/paint. The next issue, once the rust has been dealt with and new metal is in place and painted etc, is a new boot seal. They are no longer available to buy so an equivalent type is the only option.

What seals do you mean? From what I know about Automotive AC, I don’t think that using the AC all the time stops bacteria, due to how AC works moisture is created (condensate, hence the need for a drain) it’s this that can create the damp environment for mould and bacteria. Using AC all the time is better than only using it sporadically but if you don’t want any or more mould/bacteria then don’t use it at all. Switching off the AC and running it for 5-10 mins with fresh air flowing over and around the system to dry it all can help mitigate the mould and bacteria.

I always have the AC on auto, can’t speak for the previous owners though.

I've seen differing opinions on what an 'AC service' or AC clean or whatever it's actually called includes and whether it is worth having done or is it a bit of a con? I fixed my aircon leaks last year, O ring on pressure switch and the 'sight glass' slight leak. All good until a few months when during the hot weather I noticed all was not well and it wasn't cooling as it should. Also a 'smell' in the car in the morning, severity depended on what the weather was like at the time and I had it on my agenda to get the AC looked at. Last year when the MOT carried in Lexus Bolton they mentioned some dye residue on the 'other' connector to the condenser which had been checked for leaks when I sorted the AC out a month or so earlier. Residue from sorting out the AC I thought and wiped off the dye and thought nothing more about it until a few months ago. Yesterday the car was in for it's MOT, passed with no advisories, and I asked for the AC to be looked at. The technician and myself looked at the car and I explained everything, when he looked at the 'other' connector to the condenser, which had the dye residue on it last year, he immediately said it's leaking from there and it's lost gas so it's sprung a leak since I the AC was sorted last time. This particular connector was the only one that wasn't replaced last time, in hindsight I should have done this one as well. So, AC system discharged, new O ring fitted (I took a bag of assorted AC O rings with me in case they didn't have any), AC system recharged and checked for leaks. All good and AC is back as it should. That's the AC issue done. Lexus suggested an AC Service thing, I was a bit sceptical about this but they did me a 'deal' for the AC work and the AC service so I went ahead with it. I have seen a Car Care Nut YouTube video on this very subject where they pump foamy/foaming 'stuff' into the AC system via the condensate drain tube into the system round the evaporator etc and it drains out with all the crud or whatever, it looked really good and that's one of the reasons I went ahead with it. The result......................car smells great now and the stale/old car smell has gone so I'm happy with that. How long this will last I don't know, time will tell though, and Lexus said the method described by the Car Care Nut is what they actually do. It was worth having done in my opinion and I guess it should be done every few years to keep the system 'clean' or as clean as possible.

Finally got round to replacing the front KYB shocks with Lexus OEM shocks, I now have new LEXUS OEM shocks all round. The 'bouncy' thing has totally gone and the soft/smooth ride is back and the soft/smooth ride over speed bumps is back. The KYB shocks are stiffer for sure so were not as soft/smooth over speed bumps. Great for handling though but that's not what I was after. Original shocks were very much past their best but not blown, which is normally the main criteria for replacement when inspections/servicing is carried out. Body role is far far better compared to the original shocks but obviously not as good as when the 'go kart' KYB shocks were on the car but still very very good for a big car. Initially when I rebuilt the front suspension and fitted the KYB shock I assumed that the 'stiffness' in the suspension and 'stiffness' going over speed bumps was because I'd replaced all the suspension components and it would settle down after time. This was wrong, it was because of the KYB shocks being quite a lot stiffer. You live and learn, I won't make that mistake again.

I'm not sure the cost of replacing the Timing Belt is included in the 'fixed price' servicing or 'service package' cost. In the 'ECO Poster' there is a 'condition' with an * for timing belt replacement 'Additional charges may apply.....', this maybe also applies the 'service package' mentioned by Max.

For sale is a known good LS400 ECU part number 89661-50440 with a key programmed to the ECU which is very important. Fits LS400 MK4 or series 2a and I know it’s good because I had this in ECU my own car while I had the original ECU from the car rebuilt in the USA. The ECU for the LS400 MK4 or series 2a has the immobiliser built into it so you can’t simply swop it out, hence why a programmed key is important. This ECU comes with a master key with the immo ( electronic innards) programmed to the ECU, the key blade is cut but it comes with a spare uncut key case/blade. Simply get the uncut key ‘cut’ for your car, swop the electronic innards and you are good to go, then program your existing keys to your car so they all work ok. This ECU is very good and you will probably notice a difference in the way car drives. Price is £250 Buyer to pickup from BB3 area or arrange collection at their own expense.

I presume this relates to having the ECU rebuilt etc. - Relentless Motorsports is another option for the ECU and has a good reputation.

It depends what you buy. UCA's on their own are maybe 50% of UK prices landed. Other stuff is a lot cheaper compared to UK prices. For example, rear drop links - 48830-22041 LINK ASSY, REAR STABILIZER Amayama price from Japan - £24.14 UK LPD price - £192.58 plus if you buy a lot or all of the stuff you need, the overall price comes down compared to UK prices because the shipping costs are lower.

I remember looking at the original advert and thinking it looks nice, plus it's one of the last LS400's and with electric folding door mirrors. I did laugh at the comment 'the suspension looks like something from the Titanic', I know exactly what you mean. Although the suspension arms etc still 'work' (bushes are probably way past their best though), they can look really really bad, especially the rear arms and subframe. Regarding the cost of replacing. I reckon for all the suspension stuff (excluding front strut bar arms and shocks/springs) - insulators - top mounts - bump stops - front strut bar bushes - front/rear drop links - arb bushes - tie rods - front lower ball joints - camber bolts - various nuts/bolts/washers - the cost would be around £1700 plus duty and tax etc from Amayama in Japan - if everything is bought at the same time to reduce overall shipping costs. You can at least double that cost and in my view the reality is you can treble the cost for UK prices.

Maybe it's a power issue or wiring issue somehow to the tilt and telescopic ECU and/or other bits.

I had a look at this car on Friday morning last week, the eBay advert has ended now. Paint fading was worse than in the pictures, fading is to be expected with the Gold colour though. Boot seal leaking - bottom rear inner arches are going so they would need sorting - antennae needs sorting Engine bay looked ok but I didn't start the car or anything, it was only a look at the overall condition and potential 'trouble areas' before going any further and I decided not to go any further.

I wouldn’t describe a rusty arch with an inch of bubbling paint all round a ‘blemish’, I’d call it ‘rot’.

Apart from the rust and bubbling on the rear arch in the pic below.

I had a look at the MOT history on this car - N97 PPG - and in March 2021 there was a long long list of advisories - 50 in total!! I can't remember seeing a longer more in depth list, most of them are for corrosion or slight corrosion which is to be expected on a 1996 LS400. Next MOT's had no advisories at all, either everything was rectified and every bit of corrosion or slight corrosion was sorted or it was a very dedicated MOT tester in March 2021🙂

saw that while browsing this morning, I'll be up Edinburgh way in a couple of weeks and plan to have a look at the car if it's still for sale.