Please help me out! I have a 90 Lexus ls400. I had this car for about a year now. And for the last 3 months my car starts acting up. I changed the spark plugs a long time ago. And I recently replaced the starter, battery, and alternator. After I replaced the alternator my car started running again but it felt like it was about to die(shaky). That happens when I step on the brakes. It drove for a while and sometimes I would even have to jump start I don't know why but now, while I was driving down the road the lights in the car and headlights started to dim and it died on me. Turned out I blew out the 120 fuse for the alternator so I had that replaced. And now my car doesn't run. Does anyone know what's wrong with it? I'm thinking its probably loose wires but I don't know please help me somebody!!

SOURCE: my 1991 lexus ls400

The most likely problem is your alternator, the alternator charges your battery while the engine is running, if the alternator is bad you have a dead battery, but you can check with a volt meter to ensure that is your problem. Start your car (use a battery charger or jump to start it if you need to) and put your meter on the battery post's. If your reading 13volts or so your alternator is working and maintaing voltage, however if your reading starts dropping to 10 or less(may take a few moments to drop) then it's probably your alternator. You can also check your battery's voltage before starting your vechile, if the voltage increases after you start the vechile then it seem to be charging. Alternators can be repalced somewhat easily, it's only two boltsm however you do have to remove the fan belt, and re-route after installing the new alternator. If you have some expirence working on cars you can do this yourself in your driveway.
Good luck

Here's a start for you, hope this helps

SOURCE: Engine turns over but wont start

Check the cam sensor and crankshaft sensor. If either of these are defective the engine will not start or may start intermittenly.

Jamie Heppner

• 111 Answers
• Posted on Dec 12, 2008

SOURCE: Not starting replaced alt,starter,solenoid,and battery is good

It sounds like the wires from the battery to the starter solinoid are burned out, possibly even more of them to the main fuse box under the hood. You will have to start looking for the burned wires you can already smell and replace them. Starter and Battery area are a good place to start.

SOURCE: I have a 1998 Lexus LS400 with a clicking sound

You may have corrosion inside your battery cables or a loose connection somewhere.

If you have a voltmeter connect one lead to the POSITIVE post of the battery and the other to the POSITIVE post on your starter while you have a friend crank the engine
WATCH YOUR HANDS!

This is called a voltage drop test and you should see less than 0.5v on the multimeter while you are trying to start it, if you have high resistance (corrosion bad connections) you will see a higher voltage. 0.5v is the MAX you should see.

Do the same test on the ground side of the circuit, connect to the NEGATIVE battery terminal and the starter case, your voltage reading should be 0.1v or less

SOURCE: 2000 s10 Blazer dies very 3-6 weeks for no reason

i would check your ignition system. you would need a meter for this but look for broke or loose connections. if it was a fuel problem i dont think it would just start up after 20 minutes. or you might try your ignition switch. if its shorting or something then ya well it would cut your engine off real quick