I have a 1999 LHS that shuts down at any speed. Most of the time it quits after about 8 to 10 miles. It varies on how long it takes to restart usually 5 to 30 minutes. After it restarts you can finish your trip even if it is more than 50 miles with no problem. The fuel pump does run when you turn the ignition on and I have tried by passing the auto shut down relay it still won't start. There are no codes. I have read some different forums but no one seems to have an answer. I wonder if the key could be a problem because I only have one and it is the original. I haven't found any schematics for this circuit any tips or suggestions would be appreciated.

 

do have a gray key?
How or what are u using to check for codes?
Next time it shuts off check for fuel pressure and spark see which u are missing.

 

This problem is not new but it is getting worse. I only checked the codes with a cheap code reader and of course I did the self test. I have an elm327 bluetooth that I use with my laptop using different freeware but I haven't tried it lately. The only code the on board showed was P1289 but I thought I may have caused that one when I jumped out the ASR (auto shut down relay). The reason I haven't tested the fuel pump more than just listening to it run is the engine never sputters it either runs fine or it doesn't run at all. Is there a simple way to check the firing since the coils are on top of the plugs?

 

get in inline spark tester or a volt meter unplug one and one wire will have power and the other wire will have a ground pulse

 

I took the car for a short drive, about 5miles round trip and the parked it in my shop. It took about five minutes before it failed to start. With the ignition on I read no voltage from either lead to ground. I was about to try something else when it started. I then checked the voltage with it running and it was about 13.5 vdc. I replaced the wires and turned it off. I checked the codes and had a p0352 which that is the coil I had disconnected. I noticed I didn't answer one of your previous questions, I do have the gray key(it's an odd color and i think gray is a good discription.