oversteer

Lincolntran - I am also in GA and had almost identical results last week. HC was a little high but the NOx was way up there. I had the same problem last year and my mechanic cleaned the EGR system and got the NOx to pass by 1 point. This year I am WAY over at 2129 (905 to pass) and I am wondering if it is CATs. Can you tell me how your experience finally ended up?

At any point in time, several valves are always going to be open and destined for collision with a piston so there is no getting lucky with an interference motor. When the belt breaks, the valves freeze in place but the pistons will continue to move. This is true even for an automatic transmission although it is much worse in a manual tranny. In any case, it doesn't take much of a hit from the piston to bend the valves and ruin the pistons if the motor is an interference motor. In a non-interference motor, the valves can't touch the pistons even if the valve is down and the piston is all the way up. So why build interference motors? - because the smaller the gap between the piston and the valve, the more compression and horsepower you can get out of the motor. The interesting thing though is that the Lexus that the shop repaired also had a water pump seize around 80K exactly like 1990LS400 mentions in his post. Maybe this was more common than I thought.

Has anyone tried the antennas on Ebay? There are several different models being listed. One of them is 39.50 and claims to be a german made OEM manufacturer. I was just wondering if anyone had tried it. item=2432093327 Thanks, Chet

Check out www.taprecycling.com I ordered a manifold piece from them and it went well. They have a pretty big inventory of Lexus parts and send out e-mails when new parts cars come in. Prices were pretty good but all Lexus parts are pricey. Chet

Definitely follow wandawoods' advice and get the service record at the dealer. I do that before I buy any car and Lexus has a great system for seeing the history. I have found the service techs are usually pretty willing to do it for you. Lexus just implemented a new Widows based nationwide service system so I think they like showing it off. Chet

$320 is not a bad price and I wasn't able to find anything cheaper. Apparently the upper ball joints are a weak point with the car since they do wear out on all cars...they just wear out faster on the LS400. The good news is that they are really easy to do yourself so you don't need to pay lexus for labor but $640 sucks to replace two ball joints.

I agree with SW03ES. I put the Dunlop SP Sport 500 tires on my 90 LS400 about a years ago and have loved them. Excellent wet weather traction. Very reasonable wear and they have been not gone out of balance easily like some of the other tires I have had. I will definitely buy again. I got them from Tire Rack based on all the excellent reviews they had. I paid around $85 a tire delievered for 15". Paid another 12/tire for mounting and balancing. As a note: Shops usually don't mind if you bring them tired for mounting and balancing because margins are so low on the tires, they make most their money on the mount/balance anyway. Discount Tire also has local stores that will match the discounttiredirect.com pricing locally so you can just walk in and get an internet price with no shipping. Chet

For what its worth...I mentioned this in another thread. Our shop had a 1990 LS400 come in with a broken belt as a result of a seized water pump and the engine was fine. Our personal experience says they are non-interference motors (or extremely well thought of by the Valvetrain Gods :) ). Chet

My engine doesn't knock because I don't go full throttle. 175K miles and going..... Also, a knock sensor works by detecting the vibrations produced by a knock and keeping the timing retarded to compensate. A knock sensor is reactive not proactive so it doesn't prevent a knock from occuring. It senses that knocks have occured and compensates accordingly. I have several track only race cars and several performance street cars. I use 91-103 octane in all of them. Based on my driving style, I think higher octane is a waste in my Lexus. YMMV.' Chet

Nalley Lexus in Roswell GA told me the service interval for timing belts is 120K. Chet

OK...more of my .02. Remember that Octane allows for higher compression before self ignition. The more compression a motor has, the higher the temperature in the cylinder gets during the compression stroke (PV=NRT). With low octance gas, the temp could get to the ignition point before the spark starts the explosion which causes a knock. Just one thing though..... The LS400 motor is a 4.0 liter V8 that only puts out 255HP. Considering that there are 2.2l 4 cylinders delivering this kind of power, it shows you exactly how low the compression/stress is on the motor. Thats why they last so long. More importantly, the chance of detonation with low octane only occurs when the engine is under max load. This means you have your foot to the floor and are planning on getting somewhere fast. The compression on the LS400 is very low and I rarely if ever have my foot on the floor. I use 89 around town and 87 on long hwy trips. Never had a knock. Anyone who tells you that they get better mileage, a cleaner engine or more power from high octance, doesn't understand what octane is and what it means. As an FYI, I use BP/Amoco gas in all of my cars. Chet

Just my .02 with alot of experience. Synthetics are fantastic and I run them in all of my performance cars (either Mobil 1 or Redline). However, in higher mileage cars, synthetics seem to be able to find leaks better than dino based oil. If you have any leaking whatsoever, I would not recommend synthetic. My LS400 had a minor leak in a cam seal and seemed to be burning a little bit of oil as well and I decided to start running Valvoline Max Life. I have seen all kinds of snake oil in the car industry but this stuff is the real deal. Leak stopped and the oil consumption stopped. As a note, do NOT use Restore or any of that PTFE based garbage. They will do more harm than good in a Lexus.

The CD I got on ebay for my 90 LS400 was garbage. I own the electrical manual but wanted to get the engine manual so i thought the CD would be a bargain....wrong! The CD is nothing like a factory service manual and is less informative and useful than a Chilton's manual. Buyer beware. Chet

I am pretty sure the 4.0 V8 is a non-interference motor. I know somone who had a timing belt break when a water pump seized and there was no problem with any of the valves. Chet

I have 175K on my 90 LS400 and I do all my own brake work. I have used non-OEM rotors from NAPA and found that they work well but they do seem to warp a bit easier than the OEM but they are almost half the price. I figured I could get more life out of two NAPA sets than 1 OEM so that is what I have done. The big difference I have noticed is in the pad material. Stick with OEM here! Also, replace them before they get too low since heat dissipation is a pads 2nd biggest job and when they get low, more heat is retained in the rotor and they warp faster. As far as rear brakes go, I just did a complete rear brake job for the first time at 153K. I replaced rotors, pads, and parking brake shoes. The car was getting a vibration under braking and since I had just replaced the fronts, I figured it must be the rears and sure enough it was. Believe it or not, there was still a good bit of pad left on the rears. The parking shoes make life interesting if you decide to replace them in addition to the rear rotors/pads. Let me know if you need any tips on it. Chet