2002 au fairlaine

Also noticed the battery charge is lower than normal could that be the issue

Usually when backfiring is involved it's a timing chain or belt issue. Run a compression test. If all cylinders test very low or zero it's jumped timing. Hope that helps! Jim

Had similar issue...was distributor bearings worn out causing the shaft to vibrate or move excessively, throwing off the timing so would turn over but not start. Could replace bearings but due to age, replaced whole distributor. Fixed all!