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Mercury Mountaineer error code PO204, injector circuit open cyl 4
i recently replace the coil on plug on cyl 4, and it never did run much better, rough idle and some acceleration hesitation.sane as before the repair, the first code that came up was PO304 misfire on Cyl 4, then i replaced the coil and plug , after a week i got the code pO204, is they a fix for this on my 8 cyl. mountianeer.