1999 Saturn SL2 trouble starting occasionally.

check the fuel pump and or the fuel regulator......

Check earth straps on alternator and recheck connections are tight. Check any relevant fuses.

sounds like a bad starter or timing is way off poss. timing belt

Blue smoke is usually bad rings. But in the meantime, try changing your oil, see if that helps.

needs crank sensor replaced

check the alternator and the battery...

Hopefully it is only your fuel filter needing to be replace, or worse your fuel pump may need replacement. Check the fuel pressure on the fuel injector rail. You can use a tire pressure gauge, but wear eye protection, make sure the engine is off but ignition switch turned all the way toward start, and be careful you don't get sprayed.

I also have a 1999 sl2 saturn . I was having about the same problem but mine also did not want to go into reverse somtimes as well . Ichanged my fluid and filter and put in a good trans conditioner and just about all my trouble went away. The trans filter is just like a oil filter it just screws on the outside of the transmission . It is located down under the air filter housing, and the fluid plug is right on the bottom of the trans.

check your throttle positining sensor.

check to see if it has spark it sounds like it could be a broken timing belt.