Help - Car Wont Start

My Lasabre Was Shaking This Morning -98, 3.8, And Thru The Day
When I Tried To Start This Evening, It Did But Was Sound Like Runing On Half Of The Cyl
Now It Wont Start, Just Cranck
There Is Fuel - I Can Hear The Pump
No Codes On The Obdii
I Dont Know About Spark But During Cranck - Sometimes A Little Backfire, I Can See The Valves Moving So I Guess The Timing Chain Is Ok

What To Do...no Check Eng Light

Got spark to all 6 plugs, basic diagnostics?

If there are no pending codes, hard codes or history codes in the vehicle's computer to give you some direction, you may find yourself guessing at a diagnosis.

Every engine needs three things to run and idle smoothly without stalling: a correct air/fuel ratio, sufficient idle speed for the idle load, and a good spark. If any of these is lacking, the engine may stall, or not start.

You need to check for spark first! A sudden loss of spark will kill the engine cold and prevent it from restarting. The most common causes for loss of spark include hot shorts/opens in ignition coils, ignition modules and crank position sensors. Loose or corroded wiring connectors that cause a sudden loss of voltage in the ignition circuit will also stop the engine dead in its tracks.

The answer is (after repair):
Bad fuel pump very low pressure
Bad spark plugs (was told that the spark plug where burned since there was no fule)

Thanks

It was found out to be a bad fuel pump and later bad spark plugs.
Now after a week, same problem...
Good fuel but looks like bad wires...
I mesured them and found 2000 ohms to 3000ohm.
Also, I can't see spark on all the coils when trying to start
H E L P

I am having the same problem. My 92 Le Sabre won't start either. It cut off on me in the middle of driving. All of the electrical came on and then went off and left me without power anything or even hazard lights. I towed it to Sears and they thought that it was the alternator but they couldn't even test the alternator because the battery was completely dead (or so they thought). Later that day they were fiddling around with the battery and found a loose wire, they tightened it up and lo and behold the car started. I just had to pay for the diagnostic and I drove away thinking I got off very light. I drove it for 2 days with no problems then went out to my car one day and it wouldn't start. So much for a quick and inexpensive fix. What could be the problem? Is it electrical, a fuse, poor ground connection? Help!!