1994 saturn sl when i drive it loses power and shuts off

i noticed 2 weeks ago when i drive my car it loses power and shuts off
after about 15 to 20 minutes it starts back up again. even if i'm on the
highway doing 45mph to 50mph it slows down and shuts off on its on. i have
had a full tune-up,changed the fuel filter and up-graded to exspensive gas
and i'm still having this problem. so can somebody please help me?

In article
outautos.com>,
says...
> i noticed 2 weeks ago when i drive my car it loses power and shuts off
> after about 15 to 20 minutes it starts back up again. even if i'm on the
> highway doing 45mph to 50mph it slows down and shuts off on its own. i have
> had a full tune-up,changed the fuel filter and up-graded to exspensive gas
> and i'm still having this problem. so can somebody please help me?

Higher octane gas will do nothing for an engine that does not have high
cylinder compression. You can stop wasting your money on that... That is
never a fix for anything.

We could use more info such as, is the engine cold or warm when it does
this. Also I havent a clue as to what "loses power and shuts off"
entails. Loss of engine power or Electrical Power? Does it still crank?
The only guesses I have at this time are EGR, Coil pack, fuel pump, or
crank sensor. It may be off for 15-20 min but how long has it been
running prior? I'm guessing it is always warmed up?

yes, the engine is warm. when i say loses power i mean on the highway i'm
driving 50 to 55mph and it will drop on its on to 20mph and then it will
die out. i took it back to the dealer and he gave it a diagnostic test and
he says theres nothing wrong but when i drive it it breaks down on me.