I have a 1991 Lexus LS400, I will be driving it and it will up and die on me as though it is not getting any fuel, I've taken it to the shop and they are unable to find anything wrong, they said fuel pump is good, had fuel filter changed at the time I had a tune up,

I have had this same problem on many vehicles, including my own, and many times if the timing is fine, it turns out to be the Camshaft and/or Crankshaft Position Sensors failing from the heat. This cause the ignition to be cut. After the car cools down, it starts right back up. I have also had the same symptoms with a failing ECM. This is usually not the case though. You will need to monitor the Camshaft and Crankshaft Position Sensor outputs while the engine is running, and watch for the one that loses the output, or the output changes dramatically. If you have no way of monitoring the sensors during Engine operation, I would go ahead and replace them if you haven't done so in the past. This car is 20 years old, and these sensors don't normally last that long. I have had this same problem on many vehicles, including my own, and many times if the timing is fine, it turns out to be the Camshaft and/or Crankshaft Position Sensors failing from the heat. This cause the ignition to be cut. After the car cools down, it starts right back up. I have also had the same symptoms with a failing ECM. This is usually not the case though. You will need to monitor the Camshaft and Crankshaft Position Sensor outputs while the engine is running, and watch for the one that loses the output, or the output changes dramatically. If you have no way of monitoring the sensors during Engine operation, I would go ahead and replace them if you haven't done so in the past. This car is 20 years old, and these sensors don't normally last that long.

Thanks for the info I will have those sensors checked, however I did find a blown fuse in the engine compartment which was to the fuel injection system so I replaced that and so far I have had no problems with it since, but will have the sensors checked Thanks Thanks for the info I will have those sensors checked, however I did find a blown fuse in the engine compartment which was to the fuel injection system so I replaced that and so far I have had no problems with it since, but will have the sensors checked Thanks