1993 Ls400 Engine Problem

[1993lexusLS400]

I'll start by saying my dash board is broken, so I can't see my speedometer, or anything else, and my gas gauge is broken. I am very good about keeping track of my miles and making sure I don't run out of gas. Well, I didn't get very good gas mileage last week because it ran out of gas on the freeway. To make a long story short, after filling my car back up with gas, it was running fine. So I drove it to work (40 miles) in the morning, everything was fine. On my way home, however, I was in terrible traffic (I live in Southern California so traffic is a daily nightmare) and when I came to a stop on the freeway, I turned my A/C off and my car turned off! The motor just shut down on it's own! So I put it in park, turned the key to off, then turned it back on and I was able to make it home safely by staying in the slow lane and driving incredibly slow. I want to take it into the shop today, but I'm hoping someone could give me an insight as to what I can do to fix it. I'm a 24 year old young lady, my grandma gave me this 1993 Lexus LS400 with only 100,00 miles on it, and I've only put 18,000 miles on it in the last 2-3 years. The car does perform differently with the air conditioner on, but it has never done this before! I just had the alternator replaced about 7 months ago, I'm not sure if that's important? I know this car is a gem and will last me at least another 100,000 miles, so I would like to learn as much as I can about this car and would like to fix it on my own! Please, if anyone can help me, I would greatly appreciate it!

[ColinBarber]

Welcome Leah.

This is difficult to easily diagnose as it could be a number of things. When you have the A/C switched on the engine idle speed is automatically raised so when you turned it off the idle speed dropped but dropped too far and the engine stalled.

Given that you ran out of gas you may have a blocked fuel filter however I would expect you to notice poor performance when accelerating. It may just be a coincidence and it is something else. Check your air filter isn't too dirty and clogged as a start.

There are plenty of other things it could be:

dirty throttle body

bad or incorrectly set Throttle position sensor

bad spark plug

fuel pump / pressure regulator

you may also want to register and post on our sister site. There may be somebody there with local knowledge of the best place to go

http://us.lexusownersclub.com/forums/

[The-Acre]

Well there's a tough one! Do any dash lights work? The reason I ask is that a warning light may shed some, well, light on the problem. Does the engine management light not show at all, the one with a picture of an engine. Has the car lost power, if so it could be a coil pack. A little more info would be useful. Have you also posted on the US forum?

[ColinBarber]

threads merged. Please don't create duplicate topics or posts.

[1993lexusLS400]

I spoke with a local mechanic and he thinks changing the fuel filter will help, although he can't guarantee that it will fix the problem. I do have a bit of trouble accelerating, so I think that is part of the issue (needing a new fuel filter). Thank you all so much for your help!