Harky

I had the same problem...cured it by snugging down the valve cover screws. Some of the screws on mine were just finger tight. Gently!! tighten them in a sequencial pattern all the way around a little at a time. Look closely with a flashlight so you don't miss any.

I had the same problem with my 96...it was the fan clutch. I needed to buy 2 of them before I got one that worked. When your car is warmed up at idle, there should be a LOT of air blowing at idle. I saw a huge difference in air movement when i put in the second clutch. The first clutch was a china knock-off. It fit but it did not look like the OEM unit. It was smaller. and the car ran hot with the AC on. The second clutch looked different from the first - larger and much like the OEM clutch. It was more expensive, but it worked!

The whining is most likely coming from the pump rather than the R&P. I've read on other posts about bum replacement pumps. Is yours a rebuilt or a reman from one of the popular auto stores?? or is it an OEM pump from Lex?

I don't know how much difference there is between the idle control of your 98 and that of my 96....but adjusting the idle on mine is not possible by tweaking the throttle position sensor. It is more a matter of controlling manifold pressure thru use of an idle air valve. Check the vacuum hose connections to your intake manifold. I had a broken hose going down to the power steering pump idle-up valve which cause an abnormal idle in mine. The hose was brittle with age and had cracked at the barb fitting.

...[Igniters can be eliminated since I swapped connectors and checked the signal, the oddities move with the connectors!]... This is interesting...I assume that you switched both ends of the connectors...between the igniters and the coils...so that you did not produce a misfire. I don't know if a difference in the output of the coils is normal or not. If the wierd signals moved with the connectors, that would point to the connectors...right? Have you checked continuity? connector condition? broken or partially grounded wire? Also, since your problems seem to relate to throttle position, have you checked or adjusted your TPS??? Did you have it off the throttle body when you cleaned it?? How are the connections?? Check for continuity on the idle contact and a smooth linear change in resistance reading throughout the full stroke on the throttle position pot. If it checks OK, it wouldn't hurt to adjust it a little. I read in another thread that an out-of-synch TPS caused rough running. There is an adjustment procedure on the lexls.com site.

104 octane...so what. You won't get any benefit from it in a stock motor. Are you planning engine mods to increase compression? Like maybe 11:1 or 12:1...then octane boost might help.

I pulled the hoses off the the valve on my 96 LS400 and plugged them. (I have a small PS fluid leak and I was checking my valve condition.) The only difference that I noticed is that the idle speed of the engine drops a little when you turn the wheel. (The purpose of the valve is to compensate for steering load at idle.) If you can live with that, it's no big deal. However, pulling and plugging the hoses will not cure the fundamental problem, a rupture of the air control valve diaphram that is allowing oil to enter the hoses and be sucked into the engine. You have two choices...replace the valve...or remove it and plug the hole in the pump and plug the hoses.

Yup...could be an air bubble. There is a procedure for refilling the cooling system and purging the air. Don't remember the details... Have you checked in the "How To's"??

My 96 has several fuses for the A/C system. Perhaps your 90 does also... Any one of them may prevent normal operation if open. I would expect a fuse for the compressor clutch circuit. Main input to the AC relay. (I don't have apositive ID on my car) There is a fuse in the A/C - climate control circuit. (This is a 15A fuse marked ECU-B in JB2 on mine) There is a fuse in the servo (air mixing) valve circuit that could possibly be the problem (20A fused marked HEATER in JB1) Bottom line...check ALL of your fuses. Is is possible that something got shorted during your compressor swap... Good luck.

The wiring diagram for my '96 shows a 40A fuse in JB2 for the starter relay and a 7.5A fuse in JB1 (labeled "STARTER") for the park and neutral switch inputs to the ECU. I don't know if this matches the wiring on your 00 but it might be close. Have you checked ALL of your fuses ??

RE your question about the crank pulley... I've read that the smart thing to do it to break it loose, but don't completely remove it, prior to stripping the front of the engine. That way you don't loose your timing alignment. I also remember something about using the engine starter motor to break the crank pulley bolt loose...but I'm not sure of this...particularly the direction of engine rotation, so maybe someone else can verify this... FWIW, the OEM timing belt has marks that facilitate aligning the crank and both cam pulleys, so don't worry too much about holding positions during teardown.

Happi...Changing the rotors was easy. Go for it. Pull the pad pins and compress the caliper pistons by prying on the old pads before you take them out...I do it wiby hand...no tools...it gets the pistons most of the way in. Just take off the calipers, and remove the two small centering screws on the rotors. TaDa. But be sure that you check your brake fluid reservior level, if the reservoir is full and you compress the pistons, the excess fluid can spill out over the top.

Have you cleaned the screen on your rack solenoid?? If not, you may just blow out your new ACV and stress out other components in the system (hight pressure hose and steering rack seals). Pressure build-up from a plugged screen could have caused the ACV to be first to fail. Once failed, there is no way to keep high pressure fluid from leaking thru to the engine (if the hoses are connected) or onto the alternator (if the valve is "plugged").

The solenoid is located on the driver's side of the rack. You can see it thru the rear of the left wheel well. It has an electrical connection (2 wires) and wrench flats at its base for removal (tho removal can be difficult) Inside the solenoid body is a very fine mesh screen that gets plugged with gunk from the PS system. When that happens, steering effort increases. This screen must be cleaned carefully and completely. Good luck.

My 96 does the same thing...wierd moaning noises for about 30mins after driving. I tracked it down to coolant overflow (expansion) thru the radiator cap into the reservoir. Good call Thermactor.