"Check Engine: Bring to workshop" Engine Light On.

[RichRobby]

Originally Posted by JFP in PA

If you are getting P0300 series misfire codes, your coils or plugs are most likely the issue. I'd start there. And if this is the case with the codes, the Durametric is not going to tell you any more; you need to start doing close up diagnostics to ID the source.

Thanks.
Is it likely that 3 or 4 would go faulty all together?
Is there any test I can do before buying replacements and just swapping out parts?

[JFP in PA]

Originally Posted by RichRobby

Thanks.
Is it likely that 3 or 4 would go faulty all together?
Is there any test I can do before buying replacements and just swapping out parts?

Yes. Do the proper diagnostic checks, scan the car, check the coil pack connections, check the coils for cracks, etc.