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ckp controls ignition timing as well as sync.
you should be able to test with scope, engine cranking you should get square waves at roughly equal distances apart, varying due to RPM. you should have an 18x signal for ignition primary trigger and a 3x signal for sync with fuel while cranking. this is true for 3.8 anyway....
at any rate, an intermittent miss, (miss on many cyls not just one) would more likely indicate a problem with trigger circuit or ign module (or possibly pcm) rather than a coil (on a waste spark system).
you may also want to consider checking circuits for ckp sensor and circuit between ign module and pcm. there are mechanical problems that may also cause misfire. don't forget about the base engine stuff.
you should be able to check trigger with scope at the ign module and also at pcm.
you should be able to test with scope, engine cranking you should get square waves at roughly equal distances apart, varying due to RPM. you should have an 18x signal for ignition primary trigger and a 3x signal for sync with fuel while cranking. this is true for 3.8 anyway....
at any rate, an intermittent miss, (miss on many cyls not just one) would more likely indicate a problem with trigger circuit or ign module (or possibly pcm) rather than a coil (on a waste spark system).
you may also want to consider checking circuits for ckp sensor and circuit between ign module and pcm. there are mechanical problems that may also cause misfire. don't forget about the base engine stuff.
you should be able to check trigger with scope at the ign module and also at pcm.
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