92 D21 timing?

Just one more question. Could the timing be so far off that the the valves are not open when they should be? Could this be why we have so much blow back through the throttle body throat? We have taken the exhaust off before the caty conv. We have been cranking on this thing for days and don't have one drop of fuel coming from the exhaust. Any suggestions that any one has would be GREAT!!! thanks for taking the time to consider.

Thanks Again

Connie