paulo57509

Draining just the radiator should be sufficient. You do know the proper procedure on how to refill and bleed the cooling system?

The lower shaft descriptions are confusing; non-tilt, tilt, can't install it on the column, etc. I've never done column work on the LS, other than to lower it from the dash to access the ignition switch. In order to disassemble/assemble the column, I would recommend removing it from the vehicle and working on it on a bench. Hopefully, the attachments will be of some help. SR-12 Power Tilt and Power Telescopic Steering Column - Removal.pdf SR-14 Power Tilt and Power Telescopic Steering Column - Disassembly.pdf SR-19 Power Tilt and Power Telescopic Steering Column - Reassembly.pdf SR-22 Power Tilt and Power Telescopic Steering Column - Installation.pdf

What did you do to solve the problem? It might help someone else in the future.

You have a Celsior so it may be normal. It's not normal on a NA LS. My '98 has a relay in that position. Here is the circuit that contains the Engine Main Relay: From factory 1998 Lexus LS400 Electrical Wiring Diagrams Double-click the image so you can see it. Essentially, the relay powers the electric cooling fan and the front seat heater (if equipped). This relay doesn't appear to run thru any of the many ECU's that an LS has. That's why you won't see any trouble codes. A previous owner probably removed the relay as an expedient to taking the time to troubleshoot whatever the issue it was causing. Quick check: Does the cooling fan come on? If you have heated seats, do they warm?

My sincere apologies for steering you wrong. Looking back, I did remove the cam gears but left the VVTi phasers in place when I removed the cams. I did this a few years ago. Talk about a fading memory.

Did you get the cap off?

The cam plugs are sealed in place by FIPG; the top half of the plug is sealed to the cam bearing, the lower half of the plug is sealed to the cylinder head. You cannot pry the plugs out because they have a lip on the inside. When the bearing cap is pulled, they will either come out with the cap or stay with the head.

You don't have to remove the timing belt and remove the belt sprockets. The cam gears are these and you can try gently between them and the cap: What's probably hanging you up are these two plugs: They're sealed in place with FIPG; one half to the head and the other half to the cap. When I removed the cams to replace the seals behind the cam sprockets, the plugs stayed with the head. I did remove them and re-sealed them during reassembly.

This is what a dealer parts catalog shows; 90-93 use the same cable. https://parts.lexusofpleasanton.com/p/Lexus_1991_LS-400/CABLE-SUB-ASSEMBLY---SPIRAL/63176033/8430650070.html Part is NLA but at least you have a part number to begin your search.

To remove the front bearing cap, you need to break it free from the FIPG. But you need to do this without prying on the cap/head mating surface. IIRC, I did it by gently prying between the cap and the cam gears. Try to pry straight up, a little at a time until it breaks the FIPG seal. Do you have the service manual for reference? If not, see the attachments - just pick out the pertinent steps. You need to clean off the FIPG completely (see image) and only apply it where specified (see FSM). I used razor blades (don't gouge the aluminum) and green Scotchbright to remove the FIPG. Don't use power tools - you don't want to remove aluminum, just the FIPG. The washers under the four cap bolts (shown above) are seal washers. These need to be replaced and can only be sourced from the dealer. Because these four bolts have smaller shank diameters than standard bolt, seal washers sourced from an industrial supply house will not seal properly. The ID of the Toyota seal washers have a smaller diameter that works with these bolts. There are also round plugs bonded in place with FIPG at the ends of the camshaft bores. Might be a good idea to remove, clean and reseal these. EM-33 Cylinder Head - Removal.pdf EM-57 Cylinder Head - Installation.pdf

I believe you can tell by the electrical wiring harness/plug on top of the front strut towers. TBH, I wouldn't want adaptive suspension. Especially on an old LS. Replacement parts (if you can find them) are crazy expensive. When the adaptive suspension begins to have issues, most just install conversion struts that eliminate the adaptive function.

Read thru the post in this link. https://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/656360-all-my-crazy-lexus-issues-solved-ecu-leaking-capacitor.html

Because the VVTi engine is an interference design, you need to be really careful about rotating the crankshaft and cams around with the timing belt off or if the old belt was removed with the marks mis-aligned. To confirm, the sequence of events as you described are: You confirmed that the crankshaft timing mark and the camshaft timing marks were all aligned with their respective reference marks. You failed to rotate the crankshaft 50-degrees (timing mark now pointing at the idler pulley bolt). You then removed the timing belt. Now the camshaft pulleys do not align with their marks (a few teeth off). Failing to do No. 2 above shouldn't be a deal, provided you didn't willy-nilly start rotating the crank and cams around. Edit: did you remove the crankshaft pulley? Installing the new timing belt with the crank at 0-degrees and the camshaft marks lined up, you should be OK. Moving the cam pulleys a few teeth either way should also be fine. Just make sure you thread the new timing belt on per the Lexus service manual. You want the timing belt slack to end up on the tensioner pulley belt run. You confirm valve timing by rotating the crankshaft (with the belt and tensioner installed), two revolutions. The timing marks should again line up. DO NOT rotate the crankshaft CCW. Be aware for any interference when rotating the crankshaft (it helps to have the spark plugs removed).

It's not the drive gear but a good alternative. Tanin is a good company to deal with. https://taninautoelectronix.com/product/1990-1992-lexus-ls400-mechanical-odometer-assembly/

I would use them. Just check the gap (but don't attempt to adjust) to confirm they're .043" before installing them.

Looks like you need Lexus P/N 81615-87705. They look to be still available. https://parts.lexusofpleasanton.com/p/Lexus_1991_LS-400/SOCKET-WIRE-SUB-ASSEMBLY-FRONT-TURN-SIGNAL-LAMP-BODY-SPOT-LAMP/63367916/8161587705.html You don't have to buy it from the link above. I don't know why this isn't a more common, "get it anywhere" part.

Billy hasn't visited here in two years. Your best bet is to get a hard copy from an ebay seller. Or buy a short subscription to Toyota Information Service (TIS) and download it. Be advised that this is super tedious.

How many miles on the engine? Oil consumption will kill converters as well. And it doesn't have to be visible tailpipe smoking consumption either.

If you feel the need to question the mechanic, by all means do so. My father ran his own shop for +40 years in the Bay Area and would always try to explain how and why whenever a customer had questions regarding his diagnosis and fix. Did the Check Engine light come on? If it did, did the mechanic read the trouble codes that were set (if any)? If it indeed needs plugs and a coil, did he tell you why these things needed replacing? From your description, it sounds like he found a bad coil (the engine has eight coils, one for each plug). If the coil was bad, it's plug probably fouled. In these cases, it's pretty much SOP to change all the plugs and not just the one. When was the last time the plugs were changed before the rough running on the freeway (replacement interval is 90k miles)? Plugs can go bad but these days they usually go bad because something caused them to go bad. It may also be a fuel issue. I doubt fuel goes bad in a year, but it could be a "stale" fuel problem. Was the tank refilled recently? If not, remove the fill cap and give the filler neck a whiff. When gasoline goes bad it begins to smell like turpentine.

With OBDI, the trouble codes that are set don't necessarily point directly to the problem. You have two codes that indicate both a rich and lean condition, meaning the O2 sensors are reporting rich/lean mixtures that the ECU cannot re-adjust back within range. I would start looking at a physical fuel problem.

After removing the fuel cap, did you replace and tighten it? I have found this really doesn't relieve all the pressure. You might want to park the car overnight and then try replacing the filter. Generally, I usually disconnect the power to the fuel pump or remove the fuel pump relay and crank the engine over for a short moment to relieve the pressure. Typically, fuel will dribble from the line but it shouldn't pour out.

Do the cheap stuff first - change the fuel filter. The fuel filter is not part of scheduled maintenance, so unless you've replaced it, chances are it's never been changed. The pressure regulator is in the tank attached to the fuel pump. The service manual describes installing the pressure gauge under the left side pulsation damper. This sounds to me like the standard pressure test procedure. Other than the filter that's located under the body, there are a few places in and around the fuel pump where the problem may lie; the pump pick up screen and the No. 2 fuel filter may be plugged. These are supposed to be "lifetime" items but who's lifetime? Any deterioration of the rubber hoses in the fuel pump assembly could be causing a lose of pressure.

Before tearing down the engine to get to the filters, I was wondering if just removing the solenoids and spraying some Berryman B-12 or similar into the hole may clear the filter? This is probably temporary at beat but it may give some indication that debris is the root cause. Removing the filters isn't a quick job. Make sure you clean off all the FIPG (silicone) gasket material from the cap and the cylinder head. It needs to be this clean. Be mindful of where and how much FIPG you apply. Engine oil travels between the bearing cap holes and the bolts. You don't want these passages to get plugged with FIPG. Use a razor blade to remove the bulk FIPG and finish up with green scotchbright. Don't gouge the aluminum; be careful with the scotchbrite - you don't want to warp the flat surfaces. Be careful cleaning off the head - don't nick or touch the bearing journals. Before starting this job, you need to get 4 seal washers (90210-07003); get extras in case you loose some. These go under the cap bolt heads. Unfortunately, you can't use just any seal washers because the cap bolts have reduced diameter shanks and regular seal washers will not seal. The attachment might be helpful for re-assembly. EM-57 Cylinder Head - Installation.pdf

The oil control valve (VVT solenoid) filter is under the front cam bearing cap. In order to replace this filter requires getting access to the camshafts.

It's difficult to find anything definitive regarding the stuff that's inside the arc chamber. What information that's out there is that it's metallic salts that is used to increase the intensity (and color temp) of the arc. I did purchase another pair of bulbs from another source and these bulbs also have the same appearance as the ones in my original post. I'm going to call their presence as typical.