I noticed this issue more so on my mark 3 than mark 4
But I used to leave my AC running all year round so I never noticed any of this on/off.
What was more noticeable was the thud when sifting from P to D on cold engine and then there was the raw engine sound first thing in the morning for a couple or miles or so.
The LS430 is more refined in this respect so non of these exist
Have you looked here: https://www.eliteventure.co.uk/search_page.php?budgetswitch=0&make=42&model=1317&budgetmin=&budgetmax=
or this one: https://www.qualitycarstoday.co.uk/vehicle-details/Lexus-GS-450h-SE-L-U1100/
I think the difference are subtle but there:
Mark 4 Key has 3 buttons Mark 3 key is seperate from the remote
Mark 4 feels alot lighter due to electronic throttle
Mark 4 has Xenon headlights
Mark 4 heated seats are more reliable
Mark 4 has the obvious touchscreen controls
Mark 4 seats are marginally softer
Mark 4 is marginally economical due to 5th gear
For me I found that in Mark 3 I got a thud when D is engaged on a cold start - this was less noticeable on the Mark 4
Given that you have done a lot of work to your current car - if you do buy this one you will probably start checking everything and OCD wil get the better of you and you will repeat the process lol
thats all i can think of
that dial seems expensive for what it is - I remember many years buying from the same company dial kits for pajero imports - the pack used to contain speedo, rev, gear and 4x4 indicator and they used to be around £30
I think I would like to try something else in the near future - been driving cars of this era for a long time - perhaps a Mercedes C class 15/16 - I think Lexus are a bit behind tech wise
Looks like you got it looking and riding perfectly phil - lets hope no more niggly problems crop up - these cars are so silent that even your hands rubbing on the steering starts to get annoying 😃
Here are some of things u should check:
Make sure it has a full or at least a good service history which includes the cambelt change.
On driving the ride should be quite smooth comfortable with no noises or creaks from the suspension.
Gearbox changes should not be noticeable
Upon inserting key the steering should tilt and retract - test and make sure the mechanism works as motors are very expensive
Braking should be quite and smooth - if you get a groaning noise when coming to stop that’s a sign of cheap aftermarket brake pads - they will need replacing.
Check colour of gearbox oil it should be red with no smell of burning.
Check all electrics work
Check the Sat Nav works - there have been reports of some failures
Check the sound system properly to ensure no blown door speakers or woofer
Check the air suspension works - when the switch is flicked the car should rise about at inch slowly - and the compressor does not make any noises
Check the bonnet and boot struts hold the bonnet
Check the car has the correct Toyota red coolant
Check for rust around the doors near the plastic trim and around the boot area
Check rear quarter panel glass for cloudiness - this indicates the glazing has failed - mainly of pre facelift
Ask if the cabin filter has ever been changed - these are often over looked.
Check the bonnet pull works as it should - some of them fail
Check if rear aircon works - these fail due to pipe rust underneath
If the car has ACC - check it works - there has been reports of failure due to water ingress
Check the condition of the exhaust especially the back boxes - it is not stainless like the LS400
Check the door seals - due to age the outer edge starts to disintegrate
Check toolkit is present
Check if the radiator has been changed - if not factor in a new radiator as a precaution
Make sure there are no warning lights lit in the dash
Ideally you want 3 remote keys
Check the car has a matching set of tyres and wether they are branded or not - this should give an indication wether the car has been pampered or neglected
Before driving off make sure you have the say nav code and locking wheel nut key.
Check the spare wheel, jack and brace is present - this is also an opportunity to check the boot floor for water ingress
Glad you got it sorted - its the small niggly problems which take alot of trial and error to resolve
Your problem was not only annoying but also dangerous
happy and safe motoring