landar

Oftentimes when facing a mysterious problem, I find the little clues to be most revealing. And you do reiterate the above clue as well...so it might merit more investigation. If this misfire goes away as soon as you put a load on the engine then it has me thinking injector or slight manifold leak. On the other hand, you mention that P0301 happens with petrol or propane, correct? Are there two separate injectors for each fuel system? If so, then the injector most likely is not the culprit. If the injector is shared, then perhaps the injector "sticks", when cold and lightly used, until it gets a bigger electrical "kick" from the ECU, which would happen under load. Then again, perhaps there is an air leak at the manifold at cylinder #1 that seals when the engine warms. Under load, the air leaking in would be insignificant compared to the throttle air which might make the misfire disappear for the moment. I know you have performed the propane test once but I would encourage you to grab that bottle again and specifically concentrate on the intake manifold sealing surfaces of cylinder #1. I may not be understanding your comments because I just noticed in your first post that you say "This would happen ONLY when the engine was completely cold AND under load - eg. pulling uphill at low revs." Seems to be in conflict with the quote above. Can you verify/clarify? Thanks.

New Club Member, The Lucas site says "Compatible with all power steering systems and fluids, petroleum or synthetic" I even called tech support @ Lucas in CA and chatted with a service tech. I asked specifically if their power steering fluid/conditioner was compatible with a Lexus LS400 and he said "Yes, no problem". Do as you like with your power steering. I certainly do not endorse Lucas products, but I am done trying to answer with your contemptuous attitude. Guru

The cars that I have owned over the years took on a different personality when the weather dipped below freezing. Not so much my LS430 but if something is wrong with a part or system, the cold temps can definitely bring out new "characteristics". Like the PS groaning. Being that you are in for a hard freeze tonight (30F) in Sarasota then back into the 60's, you can wait and see how the groaning goes. You could always scout out the local Toyota dealers in your area. They sometimes will perform service on a Lexus at reduced rates from the Lexus dealer. Does not hurt to ask. How many miles are on your LS400?

Some have used a product called Lucas oil and believe it helps with all sorts of ailments -> http://www.lucasoil.com/products/display_products.sd?iid=273&catid=9&loc=show However, I would take that with a grain of salt. If your PS bearing truly is on the way out, nothing is going to fix it except changing or rebuilding the pump itself. You might try flushing the system and/or making sure the fluid level is correct. Have you made sure the system is devoid of air? Could be a partially collapsed hose? Filter clogged?

Just wondering if your "cow" may the air suspension pump or compressor.

Is it more like a Holstein... or a Guernsey? :whistles: Do you have active air suspension?

While not very user friendly, I do not mind pressing the "I Agree" virtual button when I need to use the map. Most of the time, I push the audio button to get into the radio settings because I use the radio much more than the navigation. The most annoying thing about the disclaimer screen is that the people I occasionally cart around seem to feel obligated to read it out-loud when they get into my car. Usually "first timers" to the Lexus experience.

Was going to say "whatever you do, don't push that button!" :o Doh, too late. Now you've done it.

No, the burned out taillights would not drain the battery. An interior light like a vanity mirror left on would affect the quiescent current.

Don't know when the last time you had the transmission fluid changed but you might want to have a quick 2 quart drain and refill. I usually do this when changing the oil. Its cheap tranny maintenance.

If the battery was charged, set for 15 minutes and was down to 60% (with a load, I presume) then the battery is shot. Why? Well, letting the battery drain due to non-use is a killer for lead acid batteries such as this. You have to keep these batteries charged up to keep from sulfation(no, I did not make that up...sounds like it, huh? :whistles: ) From your previous posts, it sure looks like you do not use the car enough to keep the battery fully charged and it is now done for(the battery, not the car). Especially if you let it go down in the cold months. From your description of things, it seems like its time for a new battery. Oh, and you do not need a 1000 CCA battery. Just put the original size battery in there and you should be good to go.

Nor was I. I was just musing over modifying the existing design as a DIY project to have separate relay contacts that are accessible. At a minimum, I could put a timed delay between the main rotor current and the solenoid to give the solenoid xxx number of milliseconds head start to engage the gears before hitting the rotor with full current.

That's a good one! And you are absolutely right. You cannot search for 3-letter words but you could put "engine oil" (in quotes) and that would work. This a volatile subject but in a nutshell, yes, the Valvoline, and whatever filter, is just fine. Go for it as it sounds like a good deal. You do NOT need Mobile 1 (coming from a guy who runs Mobile 1 and Toyota filter in my Lexus B) ).

I thought about this same issue too. My old Ford has the starter solenoid mounted on the sidewall. Now, what if I wired my Lexus starter such that the infamous solenoid contacts were always connected. Then fed the whole starter with the firewall-mounted relay? Would it work? I would, of course, leave the Lexus starter solenoid in place and have it "fire" with the starter main so that it would throw the gear into the flexplate. Actually, I know it would work, electrically, save for one tiny issue. The timing of the gear mesh and the armature turning. The starter motor would already be torquing before the solenoid had reached its full travel. Might be some grinding going on between the flexplate(flywheel) teeth and starter gear.

Jaswood, when you get a chance, you should look at the internals of the Lexus V8 and V6 engines to understand how the cams are run and how the timing belt is looped around the pulleys and the water pump. It is a pretty clever design (aside from the replacement labor). It is not a design that is unique to Lexus. A lot of other manufactures use this configuration as well..Honda, Ford, etc. As curiousB points out, it seems a bit risky to make an interference fit engine longevity dependent upon the timing belt. But thats the nature of the basic design. Now, Toyota and Lexus are going away from the belt in favor of a chain. This will help with a significant (expensive) service item on newer models.

You don't know how bad of a pun that line really is (teeth gnashing with a starter topic). If the total replacement with rebuild is $300, that is extremely reasonable. Especially if done by competent mechanics, which it sounds like you have found. You may have gotten a bad battery. It is not good to let lead acid batteries run down. It really shortens their life expectancy. Based upon your earlier post, it sounds like the charging system is good. BTW, all batteries come from about 3 different suppliers so there is really not that much of a difference. They are just relabeled and given different warranties. Lastly, don't worry about the "slow" charge, "fast" charge issue you are being fed. Your cars charging system is designed to do the correct job if you just drive it for a half-hour to hour and keep using it on a regular basis.

Yes it is possible. Unfortunate, but possible. And no, a small leak is not ok because you have an interference fit engine and if the pump goes, it can take the timing belt with it (and valves/pistons). The weep hole is put into the pumps to release coolant that is getting past the seal and into the pump bearing and to inform you of impending failure of the pump. It could be days, weeks or months of running but it will eventually fail. You will have to go thru the process of replacing the water pump again and you might as well replace the timing belt while in there because much of the cost is labor. Given the implications of a leaking pump, you might want another mechanic to verify or have this mechanic recheck to make sure the leak is not coming from a hose up above. Trust but verify. Did you use a Lexus OEM water pump or aftermarket?

Could the mechanic also rebuild the starter or is he not familiar with them? The reason I ask this is because you are going to have a little logistic issue having him remove the existing starter and waiting for the rebuilding shop to complete the rebuild. If you have the mechanic do the rebuild (again, if qualified), you put the onus on him to do the complete job correctly. If, by chance, the whole job is done and the starter wont whirl, it is his responsibility and (hopefully) warranted by him. If the rebuild shop screws up, he charges you again for labor. At the very least, the mechanic should perform a "sanity" test of the rebuilt starter before proceeding with the install. So, just some things to ponder...as if you needed more... (I know you are agonizing over this issue enough already). How much is the independent mechanic going to charge for the starter removal and replacement if you supply the parts?

You lost me there. WHY would the serpentine accessory belt go and not the timing belt if the water pump seizes? The timing belt, not the serp accessory belt, drives the water pump directly and a seized water pump bearing is either going to (pretty quickly) shred the timing belt or cause the timing to jump a tooth or more if the pump shaft leans to one side as it freezes up (as is often the case).

I believe you are correct, no EGR valve. Did you actually replace the plugs? Or just look at them? Sometimes you can not tell just by looking.

I had never heard of tapping on a starter in the LS because it is buried under the intake manifold and basically inaccessible from the outside. But I suppose you could set up vibrations by tapping at the rear of the engine that might cause the solenoid to make contact. That is what I believe he did. So, on to your questions. Does this mean conclusively that the starter is the problem? No, not 100%, just 99%. We do not know how many miles are on this starter. But it is a really, really good probability that your problem is the starter solenoid... in which case, the starter will need to be accessed. Even If you only need to "clean" the solenoid contacts(it needs replacing...the copper is gone), it still requires accessing the starter which is THE issue. Labor. Good mechanics "ain't" cheap, as you probably know. As a ballpark guess, a good mechanic could replace the starter in about 5-6 hrs. At $80/hr, you are still looking at $400-500 just for labor. Then there is the matter of the starter. While you have access to the starter, you might as well get the original rebuilt or buy a good quality replacement. Another $200-$300. So, be prepared for somewhere in the $600-$800 (or more) range depending upon who you can get to do the work. A good independent mechanic is your best bet.

I must have struck a nerve. :whistles:

Imagine you are a Lexus engineer and the boss asked you to estimate how long the timing belt is going to last. You do some figuring and come back with 180,0000 miles or 12 years whichever comes first. "Good" says the boss. "Just to cover our behinds, we are going to cut everything in half". So, its a made-up story but the point is this: Lexus has to make a recommendation based upon knowing nothing about your particular driving conditions, driving habits, climate conditions, etc. Its a "one size fits all" recommendation and that is often NOT the case. My personal belief is that time is much less a factor in belt life than mileage in the average situation. Sure, if you live in the desert, extremely dusty conditions, high ozone and so forth, the belt may deteriorate more than normal. The Lexus schedule is based more on worst case scenarios than on "normal". I changed my original 98 LS400 @ 94k and 12 years. The belt looked tired but not in imminent danger of breaking. I did quiz a Lexus mechanic about when I should change it and he said 90k miles. He did not even consider the time period. My current 02 LS430 is at 36k and nearly 10 years...still on the original belt and I have no intentions of changing it just yet. And I sleep fine at night. Much more critical is the water pump as Jim mentioned. If that part freezes up, its bye-bye belt, instantly. You should have the coolant changed every 3-5 yrs to keep the pump seals happy. I notice that the newer Lexus schedule calls for the timing belt to be changed @ 90k miles or 108 months(9 years), whichever comes first. I wonder why they changed the time schedule? Most likely due to statistical data gathered over the years telling them the 6 years was overkill. This is just my opinion of course.

As Billy mentioned, you should do a search because there is a lot of information about O2 sensors on this forum. Usually Sewell Lexus in Texas carries OEM parts for a reasonable price. You can do a Google search and find lots of sensors. It all depends upon how much you are willing to spend. Another very good site for you is the lexls.com tutorial page. Here they replaced the factory originals with some less expensive sensors -> http://www.lexls.com/tutorials/EFI/suboxygensensor.html

That makes a lot of sense, Mike. Keep an open mind for other things that are perhaps, seemingly unrelated. At 300k miles, your machine is in the heavy-use category. Connectors of all sorts can be very temperamental with age/use and could be the source of your headaches. That goes for sensors as well. It might be a good idea to invest in a good OBD scan tool for your PC. You can buy a handheld unit but those just give you the "idiot" codes. With the PC app, you can get more data and possibly glean more diagnostic info to pinpoint the misfire. If I were in your situation, I would R&R all of the plugs if you have not done so already. Despite the guessing game, I always like to start with the assumption that an issue is fairly basic and try those things first. Because they usually are simple.