2000 Bonneville 3.8 (VIN K)---- Just replaced power steering pump....and while I was at it replaced some leaky valve cover gaskets. While letting it idle to bleed power steering pump, and it had run about 15 minutes the engine just coughed and died. The engine would not restart.....though every once in a while it will "cough" like it wants to start. I checked for fuel..... no problem..... Checked for spark..... had spark........ What else am I missing?? Ideas of what I can check now.....it was running like a champ!

also, I put my Actron scanner on it and it was throwing no codes.........

How did you check for fuel?

I utilized my fuel pressure gauge.... it showed @ 45 psi pressure...... never seen anything like this before....fuel and spark.... no start.

Check your oil pressure sending unit. Which sits right below the pump. I don't remember if they are disconnected if they prevent a start.

you try moving the throttle part way? unplug the maf and try to crank it a while?tach come up while cranking?

Tried all those things, and have no tach..... sprayed starter fluid just to check..... no luck..... it was running very well....then just died.....haven't been able to get it to start since. Fuel pressure was at @ 45PSI, and my spark tester was flashing just fine.

If you have spark and you sprayed starter fluid in, something should have happened. Even a backfire.

I detected that the "spark" appeared a bit weak, so I changed the ignition module with another I had in my garage. When I went to turn the key I heard a loud bang, and looked and saw that the side of the Upper Intake Plenum had blown a hole in the side...... Lot'* a smoke a little flame so I put that out..... I'm clueless, unless I had some raw fuel in the cylinders from trying to crank the engine and when I put a "good" module on, it backfired and blew the plastic plenum to pieces??

has this car had the lim or uim gaskets or CKP changed? backfires are normally bad vacuum or wrong timing