xrayangiodoc1

Dear Fellow Enthusiasts, I recently purchased a 2006 CPO Crystal White on Cashmere LS430 with Nav and ML - and 62,000k on the ODO. Looking forward to seeing to what I can do fuel-efficiency wise. First question that occurs to me is one I'm sure has been covered before but I could not find anything using the search function. What fuel octane grade do you recommend? My most recent "other car" is a 2004 Audi A6 that recommends premium but seems to run just fine on either regular or mid-grade. It has FWD and CVT and has given years and many miles of great service. Also, any other tips for good gas mileage would be most welcomed.

I tried to economize on fuel by using half premium (93 octane) and half regular (87 octane). I figured that the octane would average about 90 and be a better deal than the midgrade 89 octane fuel. The car seemed to run fine but after about a year I noticed moderate hesitation that required an injector cleaning by the dealer (under warranty) and the advice to stick to premium grade which I have since done.

In regards to the winter driving issue (I live in the Buffalo, NY area), I put a set of Goodyear Assurance tires on and have been very pleased with the traction on snow. The tires seem to be very close to snow tire performance but are all-season. Wet weather performance has been excellent and the tire wear rating is about the highest I could find in a performance tire.

As I have reported many times on this forum, the timing belt on my first LS400 - a 1990 - was trashed in the mid 1990's at about 75,000 miles when the water pump seized. Coolant flowed from the water pump when it seized.

By the way, the timing belt replacement interval is 90,000 miles (not 60,000 miles) or 6 years - whichever comes first. LS400 timing belts rarely break from fatigue. Usually another part in the system fails - water pump, idlers, tensioner, etc. These ancillary parts should always be replaced when the timing belt is replaced. I suspect that in your case the water pump was not replaced. If it was not replaced and the water pump is the original one, getting 20 years from it is a miracle.

I owned a 1991 LS400 for 12 years. The timing belt change interval in MY owners manual was 60,000 miles, NOT 90,000 miles. When the dealer replaced the TB he also replaced the water pump and charged for it under the extended power train warranty. I just had the TB of my 2002 LS430 changed and at almost 90,000 miles the extended power train warranty was only a memory. The dealer was not automatically going to replace the water pump but I insisted on that. Also, the dealer was not going to change the serpentine belt for the accessories! I had then do that as well. I was already paying for them to remove and install those items so it just seemed to make sense to have those other major wear items replaced for just the cost of the parts!

I have not seen a good write up on this I figured I would share.

I've been witness to the slow death of one of my Low Beam HID bulbs. I called the Lexus Dealer who quoted me ~$200 for a new HID bulb plus labor to install it. After I picked my jaw up off the floor I asked if this was for the pair or each. They said each. I said thanks and investigated other options.

The OEM bulbs seem to be made by Sylvania (at least mine were) and after some research I located an OEM equivalent by Phillips on eBay. I paid ~$90 with shipping FOR THE PAIR. Then I actually had to put them in.

Note: some bulb problems are caused by the ballast going bad; mine appear to be just the bulb. The bulb would stay on, then change color (going orange) then almost completely go out. It used to last a couple minutes; by the end it was a sad dim ember.

Contrary to what I've read on this and other forums you DO NOT have to remove the headlight assembly. You do however have to remove a cover and a fusebox and be comfortable working in confined spaces that you can't see.

You will need:

• a phillips screwdriver
  
• a 10mm socket wrench
  
• 2 D2R bulbs of your choice
  
• about 30 min of your time.
  

These are HID bulbs so it is possible that there will be some residual voltage left in the system. I recommend doing this after the car has sat overnight, or wear gloves and long sleeves to help insulate yourself. Also don't stand on a metal grid or a puddle of water. And of course DO NOT TOUCH the glass surface with your hand; the oils on it will cause the glass to heat unevenly, crack and eventually melt or explode.

I didn't really take photos while I was doing it because the back of the light assembly is basically invisible; but these will help you when taking apart the car. It's far easier than it looks.

1. Remove the cover on the passengers side; there are 4 clips; two are the standard Lexus center pop-up clips, just pry the center out and the clip should come off. The two on the back both have Phillips style centers; one screws out like the pop up clips, one is just a cap that sits on top of another bolt underneath it; it will stay with the cover.
   
   
2. Remove the fusebox on the drivers side; this is a standard 10mm bolt, and then there are two metal clips that pop open on the back. You can lift this up and twist it so it sits on top of the other boxes and covers and gives you access to the back of the assembly.
   
   
3. Remove the cover- each LB bulb has a 3 inch round cover directly behind that covers the whole business; reach behind the assembly and twist this; it will unlock and you can pull it out.
   
4. Unlock the connector from the back of the bulb; it twists off to unlock. Set aside (try not to touch the inner bits).
   
5. Remove the retaining clips - each light has a U-shaped clip that pivots from the bottom and has little loops on the top. These are HARD to remove; particularly because you can't really see them. Feel around and you'll find some other parts of the clip to pull on and open them up. (I found this actually was the hardest part!).
   
6. Replace the bulb -- each bulb has a ringed collar with 2 notches in it so it really only fits in there one way. Put the replacement bulb in gently and rotate it until it seats; you'll see a little of it in the headlight behind the chrome cap and you'll be able to confirm it's straight.
   

Put the car back together, replacing the retaining clips and covers. Make sure the retaining clips and wiring connectors are sound; the bulb should be solidly in there. The pop-out clips need to be in the extended position (not the closed position) for them to fit back into the holes.

Cost of parts: ~$90

Cost of labor: ~30min of my sunday.

2 new headlight bulbs that didn't cost a fortune: priceless.

Great Post!

Could you provide the part number for the HID bulbs?

I see the same thing in a wide variety of electronics with temperature readouts. The ones that show tenths of a degree will jump by 0.9 degrees F (0.5 degrees C).

Does one need to go thru this procedure every time the car is started?

I have been using Synthetic oil since it first came out as Mobil 1. Have used it in all my Lexus vehicles (1991 LS400, 1995 RX300, 1998 RX330, and 2002 LS430) as well as my other vehicles and have never had a sludge problem. Always took the oil change interval to the max allowed. The synthetic oil is much more resistant to the high temperature breakdown relative to the standard motor oils. It also flows better in low temperatures (useful in the Buffalo, NY area). Probably also good for a little extra fuel economy.

92 LS 400 70k . This has happen 2 times before, during last summer. When I step on the gas the car seems to lose power. The rpm's go down drastic. I put it in nuetral and rev it and it sometimes comes back. It does stall out but turns right over again. It seems to get worse when it has a load against it.(in DR or REV)I can step on the gas and power is lost. Also now when I sit and idle the rpms go down, it hesitates, then jumps right back to normal. This is our 1st warm day could that be causing something to go nuts? Any advice guys..please. I don't want to spend another fortune on this prob.

Thanks JTF

Dirty fuel injectors might be contributing to this problem. I encountered similar symptoms on my 2002 LS430 which were cured after injector cleaning. Since then I pour a bottle of a good fuel injector cleaner into the tank before a long trip every few thousand miles. Also, don't try to save a few bucks by using half premium and half regular gas. Agree that the fuel filter should be changed if not done so as suggested in the maintenance schedule.