have you had the throttle body recall done? Not sure if it is in effect for the 99, but the 97 it was, and this helped fix an issue that many people had when nearing or at highway speeds the engine would die randomly. I'd research that. Call the dealership with your VIN number and they'll be able to tell you if it's been done or needs to be.
This could be many things. Did you have your fuel pressure and volume checked?
You have a broken wire.
This happened to me once - - have you checked the air pressure in the spare tire?
Have you checked the power steering pressure line?
check the bulb again, are BOTH filaments good
I got one at Michael's
Check Oil Pressure Switch. It's about $60 at Toyota
All Bulbs were replaced. fuses all checked, relay switch new and flasher, Also when the relay switch is in it gets really hot. Any suggestions
Have you checked the fuel pressure? If the pump has failed you will NEVER get it started without starting fluid.
do not now what type vehicle your working on.but check the back up light switch
Why does a person have his blood pressure checked on a regular basis?
i had the same problem but it was my fuel pump. have you replaced the fuel filter also?