landar

As concerns issue 1, you might investigate the integrity of the transmission mount and engine mounts. Your car is at an age and mileage where the rubber bushings in these components might be cracked or separated. It is easy to miss with a simple inspection. Issue 2, maybe IACV?

Wait...you took it to a mechanic and he is having trouble?? I know one thing I would do for sure. Time to find another mechanic. As good as we "think" we are on this forum, the reality is that we are just taking pot shots thru a straw. If you are not very mechanically inclined, find a good, trusted mechanic who understands the LS. They usually begin by isolating between ignition and fuel, then troubleshoot from there. Otherwise you will be throwing a lot of parts at it(think $$) in the hopes of hitting the culprit.

From that diagram, it looks like it is right behind the glove box. I can't seem to get the ToyoDIY site to give me diagrams even though I registered.

Do any of the 'cats' glow red after driving in this condition? Number 1 suspect with your symptoms is the ignition coil(s).

Did you look at the carfax history? Did you look at the Lexus dealer data base for service records? If you have already purchased the car, isn't it a little late to be questioning the mileage? I know, so many questions. BTW...Welcome!

Due to the frequency of the tapping, I would say it was in the valve train. Again, I really doubt it is the oil pump, Michael. While it is true that you bought this car "As Is", it is almost criminal for a dealer to resell it in the sludged condition. Since you are admittedly not a mechanic, the best advice I can give is to take your car to a second mechanic for an opinion on the engine condition. Take lots of pictures of any parts of the engine that are opened up to expose the sludge as documentation. After confirmation of the sludge, if it were me, I would march back into the dealer and give the owner "what for". And demand reparations. But thats just me. If you do not want to confront the Ford dealer, then you can see what can be done to clean up the existing sludge. The valve train on the LS430, being VVT (Variable Valve Timing) is very complex compared to a standard engine without VVT. And sludge is its arch enemy. Your best option may be to try to "flush" the sludge professionally. Some shops have machines to run cleaning agents through the engine in an attempt to clean the internals. But it does take special equipment and comes with no guarantees it will fix you problem(s). In fact, it could make matters worse by dislodging a chunk of gunk that later gets stuck in an orifice. Just like a stoke or heart attack. I just hope you did not pay too much for this car. Again, get a second opinion and document this condition.

The oil pump is probably the least of your worries. The Lexus mechanic took the oil pan off, saw the sludge and advised you to give her last rites. The "ticking" could be from a number of components that are not being lubricated as they should be. The metal shavings suggest internal damage that would require a rebuild to correct. At the immediate time, your 'beef' is with the Ford dealer that sold you the car. That dealership should have done an inspection on your Lexus and known about this problem...and refused to resell it to the public. You know any good lawyers?

I believe the receiver unit is located inside the trunk, left side(drivers). There are panels that need removing.

We rarely hear of cases of sludge in a Lexus. To have sludge, the engine would necessarily need to be neglected by missing scheduled oil changes and/or severe overheating at some point. I rather doubt that the Lexus dealer caused any damage. However, you mention that the dealer did change the oil and they most likely put the correct viscosity back in and the "ticking" appeared. I suppose it is possible that a thickened concoction was put into the engine prior to your purchase to mask the issue. If it were me, I would be back at the Ford dealer looking for some answers. A second mechanic's opinion would be in order.

I have changed over from dino to synthetic in my LS400 and LS430 with no leaks. Synthetic is thinner than a comparable dino weight at cold temperatures. It is most probable that some aging gaskets in your engine just need replacing and/or bolts tightened. Here is some interesting reading at "bob the oil guys" university. Enjoy -> http://www.bobistheoilguy.com/motor-oil-103/

So you're saying it's pretty darn important? Great. I'm car-less! Well, you can probably drive it, just don't expect it to perform 100% or last like it should.

It's probably not all that critical unless you want a clunk-free ride and long lasting bushings. Bite the bullet and redo...sorry.

Well, you have Electronic Throttle Control which severs the mechanical link between the gas peddle and the throttle plate (among other things). There is an electric motor driving the throttle which gets its commands for the ECU depending upon the position of your foot on the gas peddle. Maybe the peddle sensor is on the fritz. It can wear out in certain spots. In fact, there might have been a TB at one point but not sure. It is also possible that the mechanic did not properly clean the throttle body and the plate is still sticking. Did it idle erratically before you replaced the timing belt?

Assuming that you mean the electric switch works fine then that would clear the physical locking mechanisms. And obviously a radio signal is being emitted from the remote. I wonder if some anti-theft system is confused and blocking a remote unlock. Maybe disconnect the car battery overnight and see if that clears? Agreed, it is a shot in the dark. Are these the remotes that originally came with the car?

@bob, have you checked for any diagnostic codes? http://www.lexls.com/tutorials/intro/codereading.html

Could be rust in the exhaust system or possibly carbon build-up. Have you tried an "Italian tuneup" lately?

Thanks for the heads-up. Did you go back to Toyota OEM parts to resolve?

Mitchell, in my post, I mention that I do NOT believe the problem to be fuel filter or pump although these can be the culprit in certain situations. The OP can run either petrol or natural gas and reports the misfire on either which is why I generally dismiss the fuel. The OP has also tried 'sniffing' for leaks with a propane touch but has found none. Nonetheless, it might be a good idea to go over it again very carefully. I agree that the MAF sensor is highly suspect. As for the ECU, it is possible for a peripheral component or driver, even a connection, to be going intermittent. The firmware might not catch that type of failure. BTW, even though the vehicle is relatively new (2002) it has close to 300k miles.

The epic misfire and lean mixture may or may not be related. Perhaps whatever is causing the misfire is now deteriorating so badly that you have the P0171/74 codes. From what I understand, a lean mixture can also cause misfires and increased NOX output. If you have a scanner, you might see Long Term Fuel trim levels that are elevated. Causes of lean mixture could be: MAF sensor reporting less air flow than is actually there. The O2 sensors are correctly reporting a lean mixture(too much air) and this 'confuses' the computer and sets the lean codes. Vacuum leaks AFTER the MAF sensor such as intake manifold leaks, PCV leak, vacuum hoses. Weak fuel pump or restricted fuel filter. Plugged or dirty fuel injectors. Malfunctioning ECM/PCM. I believe you have already looked for vacuum leaks but you may have another go at it. Also, since you are running both petrol and gas, the weak fuel pump/restricted fuel filter are probably ruled out. Ditto for fuel injectors if the problem persists with petrol and gas. I cannot remember...did you look at the MAF?

There was a good thread on here a while back dealing with the tilt motor and gears. Let me see...yes, here it is(see post #26 in particular) -> http://us.lexusowner...+steering+wheel

It sounds like the fuse is ok. It may be your trunk wiring harness as these are known problem areas on the 90-94 LS400's. The harness is located in the left trunk hinge. You might do a little investigating to see if you can discover a broken or stretched wire.

I second the opinion of taking it back to your mechanic for diagnosis and fixing. The new problem may be entirely unrelated to the 90k work. On the other hand, maybe some sensor/connector was not put back properly. Rather than throwing ideas at the mechanic, let him/her go after it with their knowledge. Only if stumped, would I make suggestions (or take it somewhere else). A competent mechanic will know what is wrong.

Yes, there is a fuse. The fuse for the trunk actuator is shared with the fuel door opener on the later models (not sure about 94's). Try pulling the fuel door switch in the cabin to see if it will open.

Done properly, the transmission pan gasket should last forever (and ever, amen). Notice I said 'properly'. If the pan was removed for some reason, it is very easy to bend the lip and very easy for a leak to develop thereafter. The question as to whether the mechanic used a neoprene gasket or RTV-type gasket needs to be asked. The factory original is the RTV FIPG stuff. It is entirely possible that the pan bolts just need to be snugged down. And it is also possible that the 'leak' is simply tranny fluid that has run down the filler tube when the transmission fluid was drained and refilled. It is easy to spill. If you take a clean, white tissue/cloth and wipe the tranny pan, you may be able to see some red tint to the residue(tranny fluid) rather than the dark brown that engine oil usually leaves behind. Finally, what do you mean the car has not been driven hard at ALL? You just admitted to an 'Italian tuneup' in your recent smog thread. ^_^

Yes, I do believe you are correct, Billy. For some reason, I was thinking of the flexplate to crankshaft bolts. My mistake.