If you were really into trouble shooting (and old heavy fat ABSless bikes) There's only one caliper you could get a std spare line and run it lever to caliper with the abs line blocked off to see how it should feel . You could, but I don't recommend it.
Did you bleed yourself? I had issues with a bike and read a tip to wrap teflon tape around the bleeder valve threads before you crack it to help keep air from going in through the threads. it helped on that one.