No. This was in my GLH. I didn't have a fuel pressure gage. The car would haul *** in 1st and 2nd but misfire in third when the demand for fuel was greater. Chased this problem for a few years... I finally told my problem to a new tuner and he asked this question about my fuel pump set up... When I told him that I had 2 pumps in sequence in there, a small one (in tank), feeding the bigger one (on frame rail), he told me that was a "no-no"... I removed the smaller in tank pump and just used the frame rail pump (which was big enough for my setup). My issue disappeared. Lesson learned