2000 Chevrolet Express • 140 miles

My Van is the 3500 5.7 L. Was running fine up to this issue. When I crank the van I get sporadic hesitations but will not start, battery is fully charged, I have a spark (checked with timing light) but no ignition. Replaced the cap and rotor, I found some signs of wear. Used hand held diagnostic meter, no codes everything came back OK. When I attempted start up I got a major backfire out of the intake manifold, a weird thing started with this failure. When it cranks the speedometer jumps to 30 to 40 mph. But still does not start
I have fuel pressure at rail, so I tried spraying starting fluid into the intake to check possible injector fail, got backfire out of the intake manifold, it sounds like a timing issue, does the speedometer quark relate to a major computer issue or something smaller like a possible short or a positioning sensor fail?
What should I do next?
2000 express
December 31, 2012.

Common issue is the distributor lower gear wears out and the spark for the plugs goes way off. Have someone check this for you


Dec 31, 2012.
How much slap is normal? I have about 10 degrees of rotation and some vertical play. Would the mechanical wear to the lower gear attribute to the speedometer jumping?

2000 express
Jan 1, 2013.