Im getting lean codes and pinging anytime I got full throttle. The car takes 2 to 3 tries to start after sitting for an hour or so, when I check pressure at the shrader valve after letting it sit I get nothing. I cant see or smell any leaks and Im also getting the codes 51 and 96. Any suggestions as far as common places these systems leak? Oh, and its on a 92 5.0L with stock replacement fuel pump and filter 1yr ago.