Hellbrand

Hi Folks,
Brand new to the forum, and owning a LS400 in general.But heres the rundown.
I recently bought my LS off of craigslist(I know.) to replace my previous vehicle. and boy it's a step up. It's currently got 273K on it. and it was Unloved by it's previous owner. and when I say unloved... I mean UNLOVED.
Here's the Rights and wrongs.

Rights!
It starts up.
all the features work just fine.
Head-gasket is excellent.
fuel system stays pressurized
Lasted 500 miles from Cleveland to Hamilton Ontario.
Not a-lot of rust.(small bits where the wheel well meets the trim (less than credit card sized) and pockmarks (super tiny) from road travel and stones. along with a few spots of minor surface rust.
Toolkit is complete (flashlight is in-op as one of the batteries is corroded in there)
First aid kit is Complete (Needs replacement though as it's all Original... from 1997 )
Pulls Strong,
All the lights work.
Has Premium Audio(Nakamichi or Nakachimi)W/In Dash 6 disk that still works.
Interior is in Excellent Condition, Minus Drivers Seat wich i expect to be worn after 273K miles.

the Wrongs...
Had to Replace Both battery Terminals.
Had to Recap the ECU (5 of 6 done, #6 is still en route.)
Fixed 1 of the vacuum Leaks (Post MAF intake tube.)
Power Steering Only works when the whole system has warmed up.(previous owner used PS fluid not Dextron-II/III)(has since done a few drain and fills.but is still intermittent)
There's Green Coolant Rather than Red( from what I read, it needs red, I'm planning on doing a flush, hopefully it wont cause too much damage.)
Coolant Temperature Sensor never Reads past 80*C and on warm up will jump from 50 to 70.(part ordered and en-route)
O2 sensor has slow response on all banks.(up and down)
Long term fuel trim for both banks was at 37% but dropped down to %25-22~ after ECU Re-cap and Vacuum Leak Partial fix(still think there are more)
Think it's stuck in cold enrichment mode as the fuel trim only rockets up at idle now.
break wear indicator is on.(likely need new brakes)
need transmission mounts checked (just vibration at 75+ mph)(could be tires even)(Oh yeah)
Tires Need Replacement
Has an oil Leak.
Moisture in exhaust(I think that's from the Engine running too rich however. as the coolant level has not changed.)
Does not switch into closed loop mode.
Poor Mileage...(still better than my old Honda accord however!)

There's A Lot Wrong with the vehicle. but it Cleans up nicely.(Here it is at the local Canadian Tire)
(Sorry for Potato Quality)

I'm not sure where to begin with fixes. as while the list is long... it's not as long as I was expecting. and for 850 USD... It was quite the steal. and I'm enthusiastic that the repairs are coming along nicely so far. if not a little bit of a pain in the rump. sometimes)

Banshee365

Not a bad price for a decent looking car.

First, replace the last capacitor before going any further. Did you use good quality capacitors like the mother thread advises? Also, the 1UZ uses a 80*C thermostat which is about 176*F. That's normal. They run them a little cooler than newer engines. But, changing the ECM's ECT sensor isn't a bad idea. The green coolant won't necessarily hurt anything but the red coolant you hear about is Toyota long-life coolant and is preferred. The brake wear indicator is triggered when the pads get low enough to where the rotor wears through the brake wear sensor and creates an open in the circuit. Some just cut the end off and solder the wires together which will kill the light. I don't recommend that, keep the system as it was designed. Just because the brake wear light is on doesn't mean you need brake work, but check it. If you get the light and change your pads, the light will not extinguish until the circuit is completed with a new sensor. Try cleaning the power steering solenoid screen that is on the drivers side of the steering rack. You'll want to flush the power steering fluid out and replace with DEXRON ATF. To flush the system I like to remove the belt and run the power steering pump with my electric ratchet, it's much easier to do it that way when alone. Your oil leak is most likely the valve cover gaskets or cam and crank seals. Those are most common. Every LS400 has valve cover leaks at some point. The exhaust cam followers are lubed by pools of oil that sit RIGHT up against the valve cover gasket. Full to the brim. If that gasket isn't tight it leaks from there all day long. If you put a 1/4" drive 10mm socket on some of your valve cover bolts I bet you'll find many less than finger tight. That's just what they do after a while. You can try retorquing but replacing the valve cover gaskets is best.

Hellbrand

Thanks!
And yes we used the ones Yamae liked best for the ecu Recap. but we're just waiting on that 6th one!
also I like this idea for the valve covers. provided it Isn't too cold i may do this Tuesday morning/afternoon!

Banshee365

Use the Beck-Arnley kit. Very good quality. Made in Japan. I could provide you with the torque values of you would like. Revealing the semi-circular plugs during this job is also a good idea. Be very careful of brittle wiring insulation cracking off and falling into the heads. There are a few paths right to the oil pan and you don't want that.

dicer

If the green coolant is prestone, it is as good as the Toyota stuff. I have 2 running it and zero problems, its just way cheaper than the toyo stuff, and I will do the toyo stuff when things like timing belt and other such things like hose replacements etc. are done.

Hellbrand

Yeah... those were more than finger tight but still super loose... like holy crap there's a significant decrease to long term fuel trim now (20% to 1.4%) on bank 1 (bank 2 may still be tuckered but we don't know yet) and fuel trim short term on a quick spin while in enrichment mode never went into the positives at all... I'm quite pleased with this result.. thank you for the pointers... but I noticed somthing hanging off of the side of my PS pump hooked to a few vacuum lines... thinkimg this may be a IAC valve of some sort and it was disconnected from the pump I've not been too sure what to do about that...

Legender

Generally that IAC is removed and plugged. Look for additional vacuum connection locations of the big black air box that should have been feeding this valve. Just plug the vacuum feeder tubes from the box and remove the valves.. that's what most do.

Banshee365

It's called an ACV (air control valve.) They are very common to leak and cause the engine to smoke. I like to keep the system intact and replace the valve if it starts leaking. Many people just weld it solid or find the correction size bolt to plug the hole where the valve screws in. The SC400 doesn't have it and it has the same drivetrain. It is said to even out the steering feel through low and high RPM. They didn't do it on the SC400 and people that have tried it both way's on the LS400 have said that it doesn't feel any different.

Losiracer2

Also make sure to replace the crank seal. That's the first thing I had to do on my high mileage LS400 (had 255k also a 97'). Less than 2k miles after I bought it, it started coating the timing belt with oil and was leaking through the cover dropping onto the ground. After I found this I opted to replace all the seals: both cam seals and crank seal. I would only go Toyota for the Crankseal, the Cam seals i went with Felpro, they were made in Japan and were on closeout on RockAuto.

A good timing belt kit is the RockAuto Aisin one. It comes with Mitsuboshi Timing belt, Genuine Toyota thermostat and Aisin Water pump, all high quality components for under 200 bucks. Also, the Coolant Temp sensor would help restore your fuel economy. I was averaging 19mpg before and got 21-22 in my mixed driving afterwards under the same conditions. The connector on mine crumbled after depressing the connector, so it tells you how bad it was. I went to O'Reilly for this, it was 17 bucks with a lifetime warranty (Import Direct brand)

Almost all the vacuum lines in my engine bay had to be replaced along with all the connecting air bypass hoses as well as the PCV hose which was cracked and petrified rubber. Going to Lexus would be nice for the molded hoses but VERY pricey. I got a quote and for 3 molded vacuum lines, it was pushing 90 bucks with a 20% discount, so unless you're restoring to a factory show car, I would go to Autozone and try your best to find a close match. I ended up spending about 10 bucks to get all the hoses replaced in the engine compartment.

Valvoline Dex/Merc (blue bottle from Walmart) is good for PS fluid. I had a leak in one of the rubber return lines that connects to the reservoir and I filled up with that stuff. Its been good for over a year now and PS system works great with no whining or noises. Took me about 20 min of turning lock to lock, then driving and repeat to fully get the system groan free though, most likely to get all the air bled of the system.

Since our 2nd gen LS400s are pushing 20 years old, I would highly recommend replacing all the rubber hoses at once if you can since even the best quality rubber that Lexus used only lasts so long before getting heat cycled and petrified to hell in the engine bay.

I haven't yet done the ECU recap but I am getting a pesky P0770 Transmission Lockup Solenoid issue with mine that makes the car shudder when coming to a stop, I'm not sure if its the actual solenoid or refreshing the ECU would help as the previous owner said that this solenoid was done only 30k miles ago.

Goodluck on your restoration, car looks great! I've got the same color combination on my 97.

dicer

Its an idle up valve, and go to the first gen power steering bible I show how the bolt should look, a normal bolt won't work. And actually its an easy fix if the seat brass nipple in the pump in not messed up, just to replace the little o rings.

jeeps005

A good way to know if the tranny mount is causing the vibration is to put the car in park and rev the engine. Keep your hand on the shifter and if you feel a vibration @~2k rpm then its the mount.

djamps

The idle up valve doesn't change steering feel, rather it bumps the idle RPM up a notch when you're moving the wheel at idle by allowing unmetered air into the intake to stabilize idle when steering. Mine is removed and plugged and I have zero issues with unstable or drooping idle. At least for my LS, the valve was pointless and just an extra failure point.

Hellbrand

well it's been rather cold lately and my winters are on. So no updates so Far, but I plan on Doing my Cam cover Seals soon. along with sparks and wires. timing belt is still good, so I think I may just have a massive vacuum leak somewhere (maybe PCV)

Legender

If you're going to change out the PCV valve, with that many miles go ahead and order the grommet and a new hose. Trust me, if they've never been changed or been on for 100k miles you're going to need all 3 parts. I'm sure it is too cold to work on a car outside in Canada this time of year. Sounds like you've got a good start on getting this up to par.

Hellbrand

Stereo having electrical issues... radio cutting out and such... before we had a near total failure of the electrical for the car... we belive that the alternator may be failing... as its putting out 12.2v at idle and only goes higher while at higher revs... got the battery out and charging now but that's only a stopgap clearly... seems like the alternator can't keep up with the electrical system... so I have no clue what to do at this point.