I have a 2004 LS430 with 90,000 miles and no problems. Is it worth having the 90,000 maintanance or should I consider getting a new car.Lexus wants $1500 for the maintanance.

A maintenance required light means some type of maintenance is required on your car. It wont clear until the maintenance is done. Unfortunately you will probably have take it to a dealer for repair and clearing the code.

45,000 miles

it sounds like the car is a front wheel drive??
then the noise will be the CV (CONSTANT VELOCITY) joints in the front end.
these drive the wheels from the transmission but are a big swivel joint that allows the axle to turn when you turn the wheels
these have ball bearings in them and are full of special grease
they are worn out when they make a very loud clicking noise (LOUDER WHEN YOU TURN A CORNER UNDER POWER)
THEY HAVE A RUBBER BOOT AROUND THEM THAT STOPS THE GREASE COMING OUT AND THE DIRT AND GRIME GETTING IN.
if the rubber boots become perished and crack the grease comes out and the dirt and water (rain) gets in

There are many reasons why it has become so bad it needs replacing, But after its used for so many years it could produce problems for no reason at all.

Replace it and you shouldn't have any more trouble from it ..

I think 2.4l engines don't have t/belt.
as for service , look at your owner manual and see where maintanence schedule stop , go back to first page and start it from 5k miles all over.
If your book shows you svc. up to 105k miles then after that you make another round from begining.

AT 100,000 MOST PEOPLE ARE LEARY TO BUY EVEN A LEXUS, AT 200,000+ THE CAR ISN'T WORTH MUCH, I WOULD OFFER $2000.00 IF THE CAR IS REALLY NICE, BUT STRONGLY SUGGEST U ASK FOR SERVICING RECORDS LIKE OIL CHANGES AND HAVE THE CAR INSPECTED BY A LEXUS DEALER.

take it to the parts house and get the comter hooked up to the truck

if you live in the north with mountains and snow then no, but if you live in the south where it usually warm and flat lands then hell yeah good deal, these engines last awhile if you maintain them properly, i currently have 275,488 miles on my 1993 camaro i bought it since new, yeah you will have to do maintanence i went through 2 alternators and 3 batteries, like 6 sets of tires, etc but that is just basic maintanence, i also replaced the clutch twice since it is a stick shift I replace that every 120k miles, I change my oil every 3000-5000 miles my engine is still clean. I also use BG product additives during oil changes also.

My 2001 was having the same issue. I replaced the PCV valve and it fixed the problem. Total Cost 5.00. It is easily accesable but you may have difficulty finding it. It is located Left Rear Top of engine (Passenger side). Its brass and it screws in. I went online at my library and found diagram at this location. http://content.chiltonsonline.com/Repair/PrintView.aspx.

I say a factory warranty is always worth the money, but read the fine print.