I installed a Unilte with about 10 years ago and now I have a problem. It's between the unilite and the carb. I just rebuilt the carb so I think it is the distributor. It is pulling a lot of vacume and my engine will idle and run up to 50 but if I get into the Holley 4bbl it backfires and will stall. I've been told Module failure is common to this distributor and I wonder if this is the problem.