where to set timming???

[bottlebaby91]

A back firing or popping would probably be retarded timing. Check to make sure the spout connector is in, without that in the computer will not advance timing. Low rpm hesitation sounds like it could be running rich which might also explain the backfiring. If you hold it to the floor from a dead stop does it bog or sound like it wants to die? If it does than i would say it is rich, if it dosent bog, but feels powerless and than cleans up and goes i would say a lean condition, which either means the computer is not firing the injectors correctly or there is a bad injector not giving it enough fuel or a weak fuel pump or fuel filter.