20 Most Recent 2000 Lexus LS 400 - Page 8 Questions & Answers

I don't think I've ever worked on one of those... I can give you general instructions, though. First of all, you probably have some plastic covers on your engine - remove them first. Then remove your plug wires. NOTE: it is a good idea to mark them first; normally they are in specific lengths and will only fit back on one way but you do not want to mix these up! Find out what the pug gap is for your engine (most cars have the plug gap included in the info on the engine decal stuck to the underside of the hood or elsewhere in the engine compartment) and gap your plugs. If you cannot get them exact, a bit smaller is better than a bit bigger - gaps grow over the course of use from all the heat. Taking care NOT to get any dirt in your cylinders, (best blow with compressed air around the plugs first) pull your old ones using a spark plug socket (regular deep sockets lack the rubber boot that protects the ceramic). Have a look for any abnormal conditions when they come out: are they black? wet? white? all different? these conditions will tell you if there is something else going on in your engine. Check the box of new plugs for torque: usually the package will say something like 18 ft-lbs or quarter turn past snug or something like that. This is very important - tighten just a hair too much, you pull threads out of your head - tighten not enough and you risk having them be blown out. IF package doesn't say: is there a crush washer? If so, go finger-tight then 1/4 turn; if not, go finger-tight then 1/16th turn. If you can't get your fingers in there to turn the plugs in, use a piece of rubber hose stuck on the tip of the plug and spin the hose.

Take a heat gun heat up line and pinch it shut.

Well I would first ask why you would want them on. The computer grounds the fan relay when the fans are needed.They don't run until the ac is on or the engine reaches 220 degrees.Sometimes smoke in the radiator is a sign of a leaking head gasket.

The code for the sensor is the giveaway.The computer does not know how much fuel to give the injectors without that sensor working. The computer uses a factory set default reading.Assuming the cooling system is full of fluid, you should be able to test the circuit and the sensor with a meter and a scanner. The sensor is a resistance variable that takes a 5 volt reference from the computer and changes it depending on the resistance in the sensor.The sensor should read different resistance at different engine temps, and the harness should carry the voltage back to the computer. The scanner should show the sensor reading as the engine warms up.

HelloThe Engine and Automatic Transmission (not applicable to manual transmissions) in this vehicles drive train are fully electronically controlled by a computer called the PCM and TCM (Power Train Control Module, Transmission Control Module). When a problem like this or other drive-ability related problems occurs the computer stores a record of the problem (there are of course some exceptions to this, like the fuel pump, engine coolant temperature sensor and MAF sensor for instance) in the form of a fault code in its memory, to read these fault codes you must have the systems memory scanned with a special tool. Once the fault code(s) are read you then must perform the appropriate diagnostic testing to find and resolve the problem(s) DO NOT REPLACE ANY PARTS UNTIL A TRAINED TECHNICAIN HAS DIAGNOSED THE PROBLEM TO AVOID SPENDING YOUR HARD EARNED MONEY ON PARTS THAT MAY NOT CORRECT THE PROBLEM. Also always check fuel pressure for correct spec for your make and engine type.

Then a problem is occurring in the system, have the dealer scan it and see what is keeping it from starting. It may not be the alarm system, other problems may be occurring.

The voltage regulator for the alternator is located inside the rear housing of the alternator. It can only be accessed by removing the alternator and dismantling it. If the regulator is faulty it is repair by replacement usually by swapping for an exchange unit from an auto electrician. If the alternator is not charging it may just be a case of the brushes inside the alternator being worn out and requiring replacement.It will still be required to remove and dismantle to carry out their replacement.

I'm pretty sure only Ford products have a safety switch for the fuel pump.