Hello western, Super mechanic here. I just have a couple of questions about your Seville.
Does it crank over fast enough when it is giving you the no start problem?
Can you get any trouble codes from it? You would be able to see if the fuel is dripping from the injectors into the throttle body on that engine.
Well, the injectors are right in the top of the throttle body. If you hold in the off and warm buttons on the ATC, (auto temp controls) for about 5 seconds with the key on engine off, it will go through a series of trouble codes, You might want to write them down.