FiTech EFI Tuning Forum MenuForum NavigationForumMembersActivityLoginRegisterForum breadcrumbs - You are here:ForumPost History: cstangf350Please Login or Register to create posts and topics.Post History: cstangf350cstangf350UserProfilePost HistoryAny one have a clue what's causing this I have a 87 jeep 4.2 with 400hp on it duraspark distrib …In: Rpm noise problem5 years ago