1997 Oldsmobile Delta 88

I have a 1997 Oldsmobile Delta 88 with a 3.8 v6 in it. The engine absolutely will not start. I have replaced the upper intake manifold and changed the oil and oil filter due to the old intake manifold leaking coolant into the engine. All it does is pop and backfire out the exhaust pipe. This engine has over 271,000 miles on it. What would the problem be with this engine?
July 26, 2012.

Check ignition timing, check compression, check fuel pump pressure, check for a good hot spark at the plugs.

I had an issue with a 1994. It was tripping.I did all kind of stuff like plugs/wires/distributor, etc I thought it was crand sensorafter replacing all emissions items iac, etc turned out to be computer under passenger side foot area. It makes this car do all type of stuff when not operating correct. Take out and have tested.I didnt I took to a shop and after stating what I had done thats what they tried and I been riding for bout 2 months now no cuting off, hesistation. Starts everytime been riding it hard too.

Aug 25, 2012.
I have a '97 olds delta 88 v6 3.8 auto. That will run fine and is capable of driving around for a while, but as soon as I turn it off and try to start it back up it will turn over and over, but never actually start. There is no power getting to the fuel pump and the windows. It usually takes close to an hour for it to crank back up and the power to come back to windows and fuel pump. I have replaced the fuel pump, f.P. Relay and the fuse, and the ignition module. Any ideas?

Kaine Able
Sep 20, 2012.