RAINBOW

93 LS400 had complete tune-up,fuel filter and t-belt, etc. 20k ago. Anyway, driving for about 15-20 min.(@45 mph) car running fine, pulled away from light felt a little miss then engine lost power and CEL came on. Drove home on about 1/2 power(limp home mode). It runs smooth and hits on all 8, exhaust sounds smooth. Give it gas and around 1100rpm it falls on it's face. This is the 2nd time it's done this in about 3 weeks. The first time driving at 60-65 it just started dieing as if out of gas, then on again off again(half power). Turned around drove about 2 miles, engine cleared up and has run fine for 3 wks.*Just went out and started after sitting for 2 hrs. CEL still on, and engine is @500rpm. It feels fuel/air related (MAF ?) which I unplugged while the engine ran, made no difference. Any good ideas ?

EastWind

what is complete tune-up? spark plugs and wires?

how about distributor cap & rotors?

Yotarip

Hey Neighbor. I'm in VA also and my 93 ls400 did the same thing one week after I bought it (3/7/09). I towed it to my mechanic who kept it for 2.5 days trying to find the problem. Plugs/wires/ caps were changed by me just before the problem started. My mechanic changed the fuel and air filter. He checked the fuel pressure and it was good. He tried to read the code from the CEL but the light did not blink the code!!! Just stayed on. We concluded that it was a bad computer so I called a tow truck to return it to my home so I could remove the computer and send it out for repair. My mechanics pulled the panel that covered the computer and showed which haness to remove. The tow truck finally showed up and when we started my car to drive it to the tow truck, the cel was out and it ran fine!!!! It's been running fine for the past week.

This seems to be a common problem with these cars and no one seems to have an answer. It's definately not a simple ignition problem. People here have dropped alot of money on parts with little success.

I kind of suspect a problem with the harness that connects to the ECU. My car was running like yours before my mechanic grabbed the ecu harness. Unfortunately the motor was off when he touched it. I'm waiting for the problem to reoccur so I can jiggle the harness with the car running just to see if it suddenly returns to normal.

RAINBOW

My 93 is a 2 owner, the first owner took it to Flo Lexus for everthing, the 2nd PO took it to Toyota FOR EVERYTHING ! I called the Toyota dealership and they read me the service history, the poor guy must have spent 10 grand on the car ! Now I drive it for 1500 miles and the overpriced POS brakes down everytime I get in it. I did the EGR pipe(what a bi@#$) trailing arm bushings,thermostat,fog light bulb,tailight bulb,airbag light reset,etc.etc. Oh, the speakers and CD player are shot, the drivers seat won't recline,and now it turns off whenever it damn well pleases. If I had wanted another Jag or Audi I would have bought one ! Enough *****in, I hope the other Va. 93' is doing better than mine. p.s. Anyone want to trade a good F-150 for a $50,000.00 Lexus.

EastWind

Yotarip, I have had similiar problems. Changing distributor cap/rotors fixed it for me. Many people change plugs/wires but skip those.

vietunit

iTrader: (5)

I know some people that have had this problem not only on our cars, since you changed plugs and wires, I suggest you listen to EastWind and change caps/rotors. Should fix the problem and good luck.

RAINBOW

When Toyota did their thing (more than once) no expense was spared. Do you really think a dealer is going to suggest to a customer that it's time for a big service, and then just put plugs in........homey don't think so. Once it was apart they did it all. That's what I meant by a COMPLETE TUNE-UP. When it does this shut down, 1/2 power thing, it's as if you turned the key off. The car always runs perfect untill this happens. Plus the next day, there is no CEL, and it starts and runs perfect again for weeks/months. A bad spark plug or cap is not going to do this. Oh, by the way, when I got home tonight, it started right up, no CEL, and ran perfectly!!!!!!!!! That's why I'm just a little perplexed, to put it mildly. but thanks vietunit and eastwing for trying to help, and yotarip !

trukn1

Mine had similar symptoms to yours. In my case it wound up being a coil pack that went bad. I just replaced both and no problem after that. Only thing diffferent that mine did than yours was it did not return to normal operation after awhile, then again, I didn't give it a chance to and just fixed it anyway.