Next day, the situation repeats. Can't use vehicle until I resolve problem. Any ideas of where I should look?
Engine stalls after 3.5 minutes of operation. Will not restart until next day. on 1996 Lexus LS400
Do you have a check engine light on? If so codes would be stored in the computer of your car that would indicate where the fault may lie (you would need a scan tool to retrieve the codes). A professional grade scan tool would allow you to look a key sensor values as the engine fails eliminating the need for intrusive testing at each sensor. When the car fails you need to determine if you have lost fuel, spark or injector pulse. Check for fuel pressure (you will need a fuel pressure gauge and look up the specified fuel pressure for your vehicle). Remove the fuel hose that goes to the fuel rail and get a friend to crank over the engine to see you have adequate fuel volume (you should have approximately 1 pint of gasoline in ten seconds of cranking). Off course take proper precautions as gasoline is highly flamable. Next "listen" to the fuel injector. Using a mechanic's stethoscope (or use a long screw driver placing the handle end up to your ear place the metal tip end of the screwdriver against the body of the fuel injector), get a friend to crank over the engine while you "listen" to the fuel injector listen to each injector at the same point of the injector body. You should hear "click, click, click" as the injector is electrically opened and closed by the computer. If the injector is not being triggered you will not have fuel getting into the engine's cylinders. Disconnect the electrical connector at the fuel injector with the ignition key in the "on" position, (next position after the accessory position) you should have 12 volts at one of the two wires at the injector. This true for most vehicles but you need to consult a workshop manual for your vehicle to see that this is true for your vehicle. When the engine is running the second wire at the injector gets (triggered) grounded by the computer in your vehicle many times a second controlling exactly when and how much fuel gets injected into the engine. There is a company that independent auto repair shops get their information from, this same information is available inexpensively for people that work on their own cars.. The information is year make and model specific, covering repair procedures, torque specifications, fluid capacities and specifications, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate http://bit.ly/AllData_Repair_Manuals_Online
Thanks for you kind attempt to help me. Since I've received your reply, the Lexus will not start at all. I had it towed into town. Advanced Auto scanner says, "Igniter fault #2". Advance has igniters for $200.00 each (incld tax). There are two in the car. No refunds or returns. Can I be sure this is the problem? Do I need two? Thanks again for your help in this matter.