Hi I've ran the dr Prius battery life expectancy test and it gave me a warning that a weak block was detected. I also drove and tested the voltage difference and I saw it go up to 0.40 and would jump to 0.25 quite often Is that a really bad sign? I've also seen the pack voltage go to 265v and drop down to 198v. Do you think the battery could be the cause of a 6-7 mpg drop in the last 7 months? The engine sounds like its working louder and harder lately.