Does anyone know how to do an injector quantity measurement test? I got the dreaded p2ba9 code the other day, 4 days after filling with 5 gallons of new DEF. I looked around and found the post about cleaning the injector. I cleaned the injector and the port in the SRC, cleared the code and took it on an almost hour test drive at speeds up to 63mph. On the return to the house the 200 miles till no start came up. I'm thinking (again from reading) to empty some of the DEF and put some back in. I am also wanting to test the injector before taking it to the dealer. Thanks!