Graham

GrnHrnt, Did you sell a 1994 Sc400 back around 2002?

It's the transmission. You might have cooked the fluid, I would get a bigger transmission cooler for your increased HP- hot fluid is death for automatics. There are some things you can do before taking it to the transmission shop. I have a 94 SC400 (SC$00?) and had this "rev up and then engage" problem in parking lots. I found the transmission filter was factory original, the o-rings were rock-hard and cracked, so they leaked- this is like poking a hole in a straw and trying to drink through it. Anyway the filter sits down in the pan, there are o-rings that seal the connection to the valve body which were leaking on my car. The fluid is T-IV (if you go on Toyota Alldata (search the forums), there is a Lexus TSB authorizes the replacement of T-II fluid with T-IV). It is fairly simple to get in there and replace the filter. And the pan has a drain plug! :) I encourage you to reserve a weekend, I've done a lot of DIY and (taking my time) it took all day Saturday. Have fun! :)

Hi everyone, Has anyone changed their flexible couplings and driveshaft bearings? My driveshaft is still balanced (no rumble) but I can hear bearing noise when I let off the accelerator or if the car is coasting. When I got under the car to inspect, I see cracks in the flexible couplings from age and use. As for the reason I got under there, I figure the supporting bearing assy is factory with 250k miles (probably needs replacing). This car has already had all the common gremlins fixed and this car passes Mass(same as CA) emissions and safety. This is a 94 Sc400 with 250k miles. I've worked on cars for a while and can do advanced DIY (like rear axle bearings on normal cars), so I appreciate any advice! :)

I have a 94 SC400 with 250k. You're looking for records that someone always changed the oil and coolant on time! These are not miracle cars. But they will "hold" repairs unlike any other 10-15 year old automobile. But like any 10-15 year old car, a lot of stuff needs to be replaced. Brakes are expensive... there's a few links on how to rebuild calipers own your own... but brakes do last a very long time. At 150k my 94 SC needed: new struts all around new control arms and/or bushings as appropriate valve seals replaced and valve/cam shims were changed out New radiator AC system service infamous window regulator problem fixed At 200k engine repairs to fix "seeks at idle / accelerates funny" timing belt changed (was changed at 100k too) fuel filter replaced plugs & wires throttle position sensor error code (replaced from Lexus parts online) EGR valve filter is still clean (left as is) PCV valve and o-ring replaced (Lexus parts online- auto parts store PCV valves are cheap chinese crap) Sea-foam and run on 93 octane to clean faulty injector #8 (I can no longer recommend 91 octane to my SC400 friends) manual sez it's time, so transmission fluid change with T-IV (replaces T-II according to Lexus TSB) non engine: cabin air filter trunk struts replaced (40 each at local parts store, 200 EACH at dealer!) LCD screen on HVAC replaced sanded/de-schmutz the headlights repainted hood (wife used auto-car-wash, these remove clear-coat after a few years of washes) replace (or recone) factory speakers disassemble and clean volume rheostat At 250k Doh! go back into trans pan, remove filter and replace (o rings were solidified), replace about 2qts T-IV in pan. New windshield (highly recommended for night driving) upholstery replaced due to extreme wear on driver seat and sun-baking on rear seat Needs: The factory original exhaust is in need of service soon. The rear struts are showing wear. Wants: A bullet-cars supercharger to catch up to my buddy's auto-stick Audi A4 And the UZZ32 active suspension to pass him at the corners on the track If you like DIY, this is a fun car. Enjoy! :D

The cheapest fix is to recheck your wires... make sure the firing order is correct vs. the coil packs. I have seen a V8 turn headers red if two plugs are miswired. They fire during the wrong cycle and combustion occurs in the headers. Good luck

Hi guys, I took the pan off and found someone else was there before me, only 3 of the 4 magnets are there. But at 238k there was little or no metal fragments in the pan or on the magnets. The filter screen looked clean and I swapped it out with a new one.Then I added 2 quarts. One thing to note is that there is less than 1 quart between the marks. The local autoparts store had the transmission pan gasket.

Different tires have different road noise. Open sidewall is good for winter, but the escaping air makes a lot of noise. Summer tires are solid outter sidewall, so they are perfectly silent- All Seasons are a compromise between these two basic technologies. On tire rack, the Kumho tires are the cheapest ones listed for the ES300 at $82 each, nothing special dude. I feel for your situation, but I recommend that you get Michellin's or Yokohama's, part of the expense of a tire is making sure the rubber is uniform all around the wheel, as well as the quality of the rubber compound and tread pattern. (not all tires are the same, and the engineers at Michellin have access to race car tech). The winter tires will be loud too. What size weights are there on the tire? If you have a large weight on one of the wheels, but haven't hit anything to damage the Mag, then you're tire is cheap and has rubber QA problem. I drive an SC400 and QA of tires makes a huge difference. Man they get us, mine are $200 each, not $100 each. Good luck!

Hi, I have black transmission fluid, caught it in time because the car still drives. Do I put in Type T-IV (which I can buy) or Type T-II (which my dealer has in a bulk tank). The difference is I have to pay a dealer to "change transmission fluid in a Lexus SC-400" vs. "I change the transmission fluid in my driveway." Thanks for the input!

Toyota Type IV is the safest route but I'm up to try the Amsoil. Many others have tried it and I haven't heard a single complaint.. who knows I may be the first complaint but Amsoil makes good products and I'm willing to give them a shot. http://www.smartsynthetics.com/articles/au...oyota_Honda.htm Don't do it man. I lost a Chrysler Sebring Convertible because a mechanic put in Dextron "with additives" and it's an ATF+3 only transmission. Dextron is grabbier. Guess what happened? ($2000 got sent to Jasper 30,000 miles later). Toyota and Lexus manuals are specific BY MODEL. Example: 1994 Lexus SC300 - Use Dextron-II 1994 Lexus SC400 - Use Toyota T-II Hope this helps.

Update, in another forum someone suggested that black transmission fluid = slipping clutch plates. So that comes from reduced pressure... which comes from a clogged filter. Thanks for the advice guys, I'll do the "little bit at a time" from the lexls tutorial and change the filter too. I should have a shot at it this weekend, will let you know how it turns out.

Hi guys, I recently came into a 94 SC400 with 245k miles. Sometime during the past 6 months or so, the transmission fluid turned black, should I change the filter, and leave the old fluid in there hoping it cleans up, or should I also flush the fluid (and watch the seals leak even faster?) or - do nothing? I found the tutorial on lexls, and I'm fairly accomplished home mechanic, but any tips are welcome... Thanks!

Hitting the dash worked for me with the climate control. But they are light bulbs, not LEDs, so what happened is the filaments in the "dead" light bulbs re-connected. This will work until you hit another bump. I replaced the lights in my console and it is much better when the lighting doesn't change when I hit a pot-hole (there are plenty in New England).

If you let it leak too much, then you might have air in the system, so there will be no hydraulic pressure, and it won't work. You probably fixed it by now but for benefit of others here's a link http://www.lexls.com/tutorials/steering/

Here's the link. The rebuild tutorial includes how to rebuild the power steering pump for both LS400 and SC400 (they are slightly different). http://www.lexls.com/tutorials/steering/

I have the same problem in a 1994 SC400. Driving like a normal person causes a surge, and also on the highway at certain throttle settings there is spark knock. The engine is 6 months into new plugs, wires, caps + rotors along with timing chain, already tried Seafoam, but with 243k miles, it could totally be a worn-out TPS. The TRAC light and Check Engine light come on sometimes. I figured out how to read OBDI codes here: http://www.lexls.com/tutorials/intro/codereading.html Procedure: 1) Chalk wheels and set E-brake and put transmission in neutral. 2) set the desired test using the under-hood connector 3) insert key, turn to ON position 4) follow code-reading procedure from LexLS.com My SC400 reports these codes: TRAC code: 51 TRAC code: 45 ENGINE code: 41 These codes and symptoms point to failure of the "main" EFI TPS (IMPORTANT: TRAC TPS is a different P/N.) I ordered a Main TPS from PartsGeek.com, & I'm looking around for the installation procedure right now. B)