pongydoo

Has anyone ever had a valve seal problem on their LS? I am getting a blue smoke sometime when I start the car up...after a few second it is gone. I suspect it is a valve seal and since I check my oil level regularly I don't see any sign of oil leak (always full) If any of you guys has this problem, can you tell me how much to get it fixed (roughly)?

Also I would like to know what do you guys get for the gas millage? I am getting about 100-120 mile per half tank in the city driving. Is it way too low for the car? Are there anyway I can improve it?

Thank you in advance

TomWahjudi

Depending on your mileage, the valve seals might have loosened a bit. What you described is typical of valve seal, but I wouldn't worry about it since you don't even lose any oil and it only happens on start up. One thing you might want to do is to avoid idling the engine too long, this usually worsened the blue smoke a bit.

Gas mileage varies, you should do a more consistent measurement (i.e. use a tripmeter and consistent fuel filling method). This way you can say that the mileage is so and so mpg instead of per 1/2 tank. I got about 19-20mpg in mixed driving in my '95.

tenpointed

That blue smoke could be due to a leaking head gasket, which would allow anti-freeze to mix with the oil. I hope it's not for your sake because it's an expensive fix due to lots of labor.

Gabeshell

Blue smoke in the exhaust typically indicates burning oil. If the smoke is white then generally the smoke is burned antifreeze. Beside valve seals you can also check the oil returns in the heads. To check this all you have to do is take the valve covers off. In the front and back of each head there is a small hole. This allows the oil to drain out of the valve covers back into the engine. If the return holes are clogged, or even partially clogged an excess amount of oil accumulates in the valve cover and it forces it's way past the vavles and is burned off in the combustion chamber. I found this out the hard way on another vehicle I owned. This is a simple fix, if it is the problem. I ended being told that I needed a new motor and followed that advice. I could have saved a lot of money by checking the return holes.

RODDMOD

Check for a leaking Idle control valve off the power steering pump, pull the hoses of the intake and loop a piece of hose to the now open intake ports and see if your smoke problem is gone.

pongydoo

I'm not currently losing any coolant level as well as oil but if I have time to check the hoses later on I will anyway.... I just had the car inspect last 2 months at the local Lexus dealer for a 3000 miles road trip and they said that it is okay (nothing to worry about), so I assume that there are nothing serious, the car has 100k + mile

And as far as the gas millage concern I get about 11-12 mpg city driving and about 12-14 city/highway and about 15-16 mpg for highway. (not driving hard at all (normal driving)) Is it way too low for the LS400?? Are they anyway I can make a millage a little better (I had the car for 2 and a half years but I never pay attention much on the gas millage until recently)???

rybikowsky

my 1992 ls400.was smokeing just little when I started it after setting for a few days.I changed to mobil 1,and in a short time no more smoke at start up.

pongydoo

rybikowsky, how many mile on you Lexus???

rybikowsky

one hundred thousand miles

Pilot

I would change oil, and add 1 QT of Marvel Mystery Oil (Wal Mart). Run this for about 1000 miles and then change oil again. MMO will gently clean carbon deposits from inside the engine, and very well could stop the oil burning. MMO will clean carbon deposits on the piston rings, and groves. I have been using MMO for years in every engine I own. There is tons of info on MMO all over the Internet on the benefits of using MMO in the oil, and also 1 oz per gallon in the fuel to clean the fuel injectors, and overall fuel system.

I have a chevy van I bought with 120,000 miles. It was smoking when I bought it, and after treating with MMO for 1000 miles in the oil and the fuel, it stopped smoking. I now run Mobil 1, and it uses no oil!

I talked to an aviation mechanic who recently overhauled a small aircraft piston engine. The mechanic could not believe the engine could be so shinny new inside, but yet due for overhaul by the hours accumulated. He asked the owner about this, and the owner said he used MMO occasionally in the oil, and the fuel. The mechanic said the pistons, rings etc where as clean as new. They showed signs of wear and were replaced, but he was amazed at the absents of carbon on the lower piston skirts, rings and ring groves.

Pilot

pongydoo

If I run synthetic on my car (such as Mobil1), but my car has higher millage, will it generate any problem? Someone told me that if you have higher millage car, don't run synthetic!!!

Anyway, pilot I will change my oil this weekend and try Marvel Mystery Oil and see if it will cure the problem ..thanks guys

Pilot

Generally I agree with high mileage cars you should not run synthetic oil. I normally recommend a synthetic blend, which is a little of both worlds, so to speak. This will prolong the life of the engine and the synthetic blend will prevent additional carbon buildup. With all of this said, the LS-400 engine is one the best designed and built engines in the world. I have read the book on the history of Lexus (Lexus, The challenge to create the finest automobile, by Brian Long) and learned that Lexus designers built and tested almost 1000 engines before any production cars were ever built. The engineers attempted to destroy each engine by running them under full load at high RPM's on a test stand, and then built each future engine even tougher. There are pictures in the book with LS-400 engines running on test stands with cherry red exhaust manifolds! Lexus engineers were hell bent to build the finest engine in the world, and I think they succeeded. For this reason, I believe if you clean up the inside of a LS-400 engine you can run synthetic oil. My LS-400 has 135,000 miles on it. When I changed the timing belt, I changed both cam seals, and the front crank seal, as these seals are exposed and only cost about 10.00 each. They take only a few minutes to change when they are out in the open during a timing belt change. I also replaced the rear engine seal after I discovered an oil leak when I first purchased the car. Now that I have all new oil seals, I choose to run Mobil 1 oil. There is a chance of oil seal leakage on old seals when you run synthetic oil. The synthetic blends will not do this. I would like to mention few Lexus mechanics have ever seen the inside of a LS-400 engine. They simply do not fail, and are still running, unless the car has been wrecked etc. When salvage yards attempt to sell these engines on Ebay, they usually sell cheap or not at all, because few Lexus owners need an engine! I think more people would retro these engines into other older cars, and kit cars, if they only knew how strong and reliable they really are.

Pilot

pscmj

I know I’m getting off the subject of this thread, but I too am a fan of the LS400 engines (but not to the extent I used to be). I have heard the same stories about how Lexus engineers tested these engines to the point of destruction so they could make them better and better. They are without a doubt one of the quietest, smoothest, most powerful (per liter) and most durable engines available for mass production vehicles. Also, I might add that highway cruising gas mileage (I’ve averaged ~26mpg @between 70-80mph in my �E4 many times) is phenomenal. However, that is where my praise ends. My disappointment, which has been confirmed by several other posts on CL, is in the seeming inability of Lexus dealership technicians (and anyone else for that matter) to diagnose and eliminate the hesitation problems associated with some (not all) of these engines.

My �E4 had three main problems with hesitation, one at take off from a standstill, one while going up a small incline, and the other while going down a small incline. These were all very inconsistent problems, but very noticeable when they occurred. Several trips to the dealership accomplished nothing. I was however able to at least eliminate the third problem after reading the post by Lvangundy about his experience with a new part number TPS. This problem would occur when I would ease up on the gas just to maintain speed going down a hill, but not totally let off the gas; however, the engine would respond as if I had totally taken my foot off the gas. I soon learned that if I left my foot in the new position, the engine would respond after about 2 seconds. This drove me nuts. The Lexus technician I talked to (who had been with Lexus since they started) was very aware of this problem, and said the way they “fixed�Ethe problem was to adjust the TPS so that the problem wouldn’t be exhibited under normal driving conditions for that driver. Not a good fix for me since my daily commute covers many different driving conditions. I suggested replacing the TPS, but he said that would be a waste of money since they had tried to fix this problem many times by replacing the TPS, but were never successful. He explained that there was an inherent dead spot in the TPS and that’s what was causing the problem.
The other two hesitation problems remained. That same tech and another tech I was able to talk to at the dealership knew of the other problems as well. Again, they said this was “normal�Efor the �E4. They even called Lexus on my behalf while I was there to see if there were any new fixes, but of course there weren’t. I guess I’m lucky in that all I had replaced was the spark plugs and wires before they admitted that the problem couldn’t be fixed. The car had ~86K miles and had had the 60K service performed at 75K �EI was the second owner and went ahead and had the 60K done shortly after I bought it. Anyway, once they told me the problem was inherent or “normal�E I got more than a little upset with them considering they charged my $400 for the plugs and wires. After a rather lengthy conversation with the service manager about the entire issue, I was able to negotiate with them $200 (half the plug/wire job) plus a 15% discount (according to them, Lexus offers a 15% discount on parts after 90K as a appreciation to long time owners) on the replacement of the instrument panel circuit boards (that is another touchy subject with me). I am very glad that the fine folks here on CL were able to get to a solution for the IP problem.

I know I’m rambling, but once I get going, it’s hard to stop. Again, let me say that I think Lexus engines are among the best in the world, but these annoying problems cast a cloud over my overall driving experience, and from other posts on CL, I know I’m not alone. Every time I read that someone has been told that some condition they are posting has been deemed “normal�Eby their local Lexus folks, the hair on the back of my neck begins to stand at attention. I guess you now know why I sign my replies the way I do.

Pilot

Geez, I am sorry to hear about these problems! My 91 LS has 135,000 miles, and runs very smooth in all driving conditions. It is hard for me to believe that your 94 LS was acting this way when it was new off the show room floor. If it were, I would think the first owner would have pulled a hissy fit, and either not bought the car, demanded another car, or attempted to have the dealer fix the problem. If these problems were not present when the car was new, then it has to be possible to return it to the same condition. I wonder if and where there are Lexus mechanics who can fix these problems!

Pilot

pscmj

Pilot,

Those were my exact thoughts, and still are to some extent. Although after a few lengthy discussions with the techs, I began to realize they weren’t trying to avoid the issue, and maybe this was inherent in some of these cars. They told of situations where when these cars were new and under warranty, they tried various things, but never came up with a real fix for these hesitations – and neither did Lexus. All they could do was “move” the problem by adjusting the TPS. They began to talk about possible replacement of the ECU, EGR valve, etc. Unfortunately, Lexus parts are too expensive to just be guessing (“shot-gunning” as we call it the electronic repair trade). On my own, I replaced the EGR valve, but that didn’t help, and thankfully I was able to return it for a refund. And, as I stated in the other post, I did replace the TPS, which did eliminate one of the problems, but the hesitations were still there. I ran gas treatments through many tanks of gas, no help, and I know the throttlebody was cleaned at the 60K service. I finally gave up.

Anyway, to make a long story short (I know, too late), I traded the car in on a 2000 RX300. The LS was quickly approaching the dreaded 90K service, needed front-end work (those dreaded popping noises were becoming more frequent), and struts at each corner. Our family needs changed to where we needed an AWD, and they gave us a great trade-in allowance. I kept an eye on their lot, and know that car sold in less than two weeks (it was a beautiful anniversary edition with only had 88K miles). I now drive a Chrysler mini-van … maybe those hesitations weren’t so bad after all