Jack Peck
Member
2000 Mercury Optimax DFI revving up to 5000 rpm at initial startup for approx 5 seconds, then settles to normal idle approx 650-700rpm. Seems to only happen when engine in cold. Put on diagnostics, no warnings/issued noted. All system checks show "passed" Have all detail of diagnostics printed out. Any suggestions for a starting point to troubleshoot this issue will be greatly appreciated.