Have a 2004 Saab 9-3 Turbo with a manual transmission. It cranks but does not start. If I tow and pop the clutch, it starts and runs like always and of course gives me a check engine light for a couple of days then goes away. It then starts like normal for about a week and then cranks without starting and I repeat the process. No codes are being stored and I'm at a loss of which component I should replace. Thanks for the help.