Thanks to those that helped me diagnosis my 92 SC400. The fuel pump ECU lasted about 100K miles.

Here were the symptoms:

The car would start when cold.
It would not restart after it had been driven. It would need to sit for a couple hours.
In it's feabile attempts to start it was starving for gas and the engine would shutter and shake then die out.
It would not die while driving but simply wouldn't restart after it had been driven for a while.

Here was the solution:

Found a used FP ECU from a 93 SC400 on ebay for $68 and had it shipped next day. All in all it cost me less than a $100.
Took out the back seat and the back driver side panel.
The Fuel Pump ECU is located right behind that panel.

It took me no more than 30 minutes to take it apart, replace the ECU and put it back together.

It is running perfect now.

Thanks for the input!

 

There was a DIY for this, where they connect 2 wires from the fuel pump ECU.

 

I saw that. It was to bypass the fuel pump ecu and have the fp run at 100%

 

This is why we have an engine forum.

Moved

 

And that is why there are mods to let us know these things! Thanks