I am not familiar with the codes anymore, but it may not be the pump. I found a list of the codes on the net before and I am sure you can, too.

The prices may have come down, but when I changed my VP44 I thought I got a good deal at $1,200.00 exchange

Bear in mind that was 4 or 5 years ago and like I said the prices may have come down because the VP44 is not the newest design now. I did mine myself and had never done more than oil changes to the Cummins before that. You can do it, too. There is lots of info out there about the job. Be sure to upgrade the lift pump if you have not already done it.