62Daytona

It is sad to see how fast SC Lexus cars loss their value. I found a 1992 SC400 with 75,000 miles in TX for $3500! I can tell from reading the description that the Main computer's capacitors are leaking causing all sorts of problems. The car looks brand new. I could take my car's ECU and plug into this car and it would drive normally. Found another 92 SC400 with 65k miles for $4800-one owner! This month I've spent $1800 for all OEM rear control arms, $200 HP Tokico rear shocks, new rear strut mounts $86, rear sway bar bushings $30, rear Sway Bar Links, $80, Tanabe Coil springs NF210 $216 set, bought a new used Cluster with good needles for $80 (installed new back lighting bulbs $16) . That's about $2212 worth of parts for my 1992 SC400. My trade-in value is about $2000. I've tallied that I've spent about $4600 fixing my car over 16 yrs. I still need a windshield. I guess I'm keeping my car another 16 yrs.

I pulled my cluster out of my 1992 SC400. Back in 2005 I got 32 LED bulbs installed and a single red led on each needle. Some of the bulbs have quit working so I thought I would refit OEM bulbs and see about added new Tannin needle kits. Well, I was disappointed how my Boards looked and I don't think the solder can be removed from the circuit board. The needles cannot be up graded either. The short needle is for fuel and the center pivot is broken, probably won't hold a setting. My question today is how to calibrate the needles? I removed them all and reinstalled them. The fuel gauge was always off 1/4 tank. The RPM now sits on Zero at idle. I left off the Smoked screen so I could the needles during the day. Remedy, I found another cluster with only 79,000 miles and it looks like it is original and not molested. What do I do about the mileage difference? I have 162,000 on mine. Go to DMV and explain the difference?

I've been reading of the capacitor problems that LS400 clusters have. Does SC cluster suffer Capacitors problems, too?

resisters were added to the Speedo & Tach shafts. Also resister on each side of first board. I reinstalled the cluster and left off the Smoke Cover. Tomorrow I will see if I can see the needles. I'm searching for another cluster.

Old thread brought back. I had Le*te*h install a 32 LED cluster bulbs and "Waterfall" needles in a Group Buy thru the other site in 2005. Some of the bulbs have quit and the needles can only be seen at night. I took the Cluster out today and separated the boards and found a Nest of solder and resisters. Can I reverse this or do I need another cluster? The needles have glue all over them. What can I use to soften glue?

I found the Thump in the Trunk . I found the driver's side Strut Mount has broken. The shock nut floats up/down. Passenger side OK. Temporary fix-a big washer. Original Strut mounts lasted 25 yrs and 162,000 miles. Ordered rear strut mounts from Rockauto.com

I found this photo years ago. Lexus built their best cars the first year. Must impress the Public. My 92 SC400 is at 162,368, but I haven't driven it in several years. Chasing the "Thumping Noise" in the back-more parts being replaced.

I have a 1992 SC400 lexus with 162,000 miles. I've owned it for 16 yrs. I replaced the rear shocks with HP Blue Tokico and sway bar links. The rear suspension makes a Thumping noise like something was loose in the trunk over sharp bumps-cracks in concrete. So then I replaced the 2 lower control arms with new Lexus items on each side. The noise is still there. I have the upper control arms but have not installed them. The uppers will require dropping the subframe a few inches. I lubed the sway bar bushings-no help. I used all new bolts/nuts and torqued them. I wonder if the rear springs are weak? What about the Strut Rod bushings? What about the 4 subframe bushings? What about the 2 Differential bushings? What about the Driveshaft center bearing mount? I replaced all the control arms, shocks, sway bar links, tie rod ends and sway bar bushings in the front. I replaced the Transmission mount. I have all the maintenance records covering this car. In 1995 with 30,000 miles the previous owner complained of a thumping noise going over bumps. Lexus solution was to lube the front and rear sway bar bushings. I read other Lexus Car forums and it seems that Lexus models emit suspension noises. I'm asking anyone who has had this problem and found a cure.

The front lower control arm bushings will be broken. Has the Timing Belt been replaced? The water pump is driven by the Timing Belt. At 60,000 miles the service is to include-spark plugs, timing belt and valve clearance check. Timing belt can last 100,000+ miles, but 152,000 miles and 24 yrs is really pushing it. I have a 92 with 162,000 miles. I've had it for 16 yrs. Several items need attention. I'm replacing all the rear control arms because the bushings are hard and the bolts are frozen. The back control arms were $1800. Check to see if any OEM parts have been installed in the last 24 yrs. I had to replace part of my TRAC control system, it was $1000. OEM parts for these cars are very expensive. Replaced my Fuel Pump Control unit, it was $368. I did the work myself. Get complete shop manual(s) if you plan to keep the car or work on it.

Are there any codes? Does the engine stall at idle or under load-driving? Did you replace the fuel pump control unit? An easy fix for a bad fuel pump control unit is to use a piece of wire and connect FB and B+ together inside the engine diagnostic box. Have you checked you TPS? If you have TRAC control, then you have 2 TPS. They are located on the Intake near the manifold. The first one on the left controls the engine system, the next one on the right controls TRAC. Another maintenance item on the SC400 is the idle speed valve on the front of the intake manifold. It has an electrical motor that controls air at idle. Mine had carbon build up. My car had 155,000 miles when I found the buildup. You have spent a lot of money on parts you probably do not need. I would bite the bullet and take it to Lexus and get an estimate to repair the problem. Since your car is so low mileage it is probably Carbon buildup someplace. Keep the car after you repair it. No other car can replace it under $30,000.

I replaced my ECU March 2015. All is well. I believe the faulty Capacitors used in our ECU's are the problem. Many owners are repairing their Main ECU's capacitors. Tannin can do this for you. He has a EBay Store. Do NOT be tempted to buy a USED fuel pump ECU. Here is the inside of the Fuel Pump ECU. I suspect the Blue Capacitor is bad.

I had a similar problem with my 92 SC400. A simple check to see if the problem is the Fuel Pump ECU is to use a jumper wire at the diagnostic box on the engine. Use a piece of copper wire bend into a U and plug into FB and +B. Look inside the box's lid to identify connectors. This supplies 12volts to the fuel pump when the Key is ON. If this solves your problem then the Fuel pump ECU is bad. They are about $380. The Fuel pump ECU is located under the left rear passenger panel. Give it a try, it is free. A bad Fuel Pump ECU does not set a code.

to check if the fuel pump ECU is bad, open the code connector box on the engine, use a paperclip and connect FP and +B (these are on the left side of the box. This allows 12 volts to the fuel pump. If the engine starts and runs OK the fuel pump ECU is bad. If your engine dies in traffic this remedy should work so keep a paperclip in the console. A toyota mechanic said that most fuel pumps quit between 130-150,000 miles. I would replace the fuel pump and the fuel pump ECU at the same time. They are both wear items. I have been chasing a similar problem. I have NO Codes in the system. I cleaned and tested the IAC valve and the EGR valve. Now I'm testing the fuel pump ECU. I have 153,000 on my SC4 and know I am a candiate for more new parts. The SC400 qualifies as a "Cash for Clunker" program, but the vehicle as a whole is worth much more. My TPS was replaced @100k by Lexus dealer when my TRAC light came on.

Have your problems been fixed? Have your mechanic check the Fuel Pump ECU.