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Hi, this is my first post, so be gentle. My Civic is showing an engine check light, and my local garage found a diagnostic code 22-4. They had no idea what this meant, and cleared the light, but it has now come on again. Does anybody know what this means and how serious it is. I am going to struggle to get to a Honda dealer and need to know if it is safe to use the car, or if there is anything I can do.

Thanks in advance for any help