I've got a 1998 Lexus LS400 with 169,000 miles on it and I have maintained it since I purchased it with 70,000 on it. I replaced the starter 2 times, done complete brake jobs numerous times, replaced all the fuel injectors, pulleys, belts, gaskets, and cleaned the parts that were taken off when I replaced the starter. I replaced the timing belt around 150,000 a few months ago. Now I am going to replace the brake booster and master cylinder. I think I've got all the info I can get from the internet and a copy of the service manual. However, there is a small plastic square device up under the left side dash attached to some mounting device which I have to remove in order to access the 4 bolts holding the brake booster. This device is gray in color and is about 3x3x1 inches. I cannot find any info about what this device does and how to remove it on the internet or youtube. There is nothing about it in my copy of the manual. Alldatadiy.com might have some info on it but I do not want to pay the $30-$50 for a membership to find out how to deal with this situation. Please help me if you can.

 

Tilt and telescoping ecu?

 

I have a 1999 LS w/ 272K miles, was wondering what prompted the master cylinder and booster change. Mine are original. Replaced starter a year ago for the first time.

 

Thanks for the info about the tilt,telescopic,and PS ECU. My downloaded Lexus manual pages BR-18 o BR-21 which covers the brake booster shows the ECU in the components diagram and the instructions. I first checked the internet and looked at a video of a guy removing a booster from a 1997 LS400. The video showed the car with the dash already disassembled and the removal of the 4 booster nuts but not the ECU. I have copies of 2 manuals for the lexus. One is from a LS400 shop manual and the other is a manual written in sections with each section containing generalized instructions on different models (ES300,GS300,LS400,...) with only instructions to remove the vaccum tube, pedal return spring, push rod clevis pin, and 4 retaining nuts for all models. Unfortunately I grabbed the generalized manual to start work. When I discovered the ECU unit I made the entry in the Lexus Club. I should have first checked the more detailed manual and will do so in the future.

In any case, Thanks for your help.

Regarding replacing the booster, I have noticed the the brake pedal has been generally softer when I start the car and when putting on the brakes. So I did the following test: I pumped up the brakes several times and when I started the car, the braked pedal went down more than a inch. I then let the car idle for about 5 minutes, pumped the brake pedal a few times and when I cut off the engine, the brake pedal started going down. I then decided to replace the booster and master cylinder since the car has 169,000 miles on it.

Regarding replacing the starter. I bought the lexus at 68,839 miles from the local BMW dealer who previously sold me a 1998 BMW 528i which I also maintain. Approximately 2 months after buying the LS400 the starter failed at 70,125 miles. At that time I had a local shop replace the starter along with the timing belt and waterpump. The repair shop said that the starter on a LS400 was a weak point.

The starter failed again around 150,000 and I replaced it along with the timing belt, waterpump and other stuff.

Again, Thanks for you help.

 

ive owned two LS400S and the first starter made it to 300K I’m shocked yours blew out at 70