Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
Usually when a vehicle is in a flood, the coil holes get full of water which can cause a misfire. Also, the spark plugs could be fouled from the water. It would be a good idea to change out all of that or at minimum make sure its dry. After that, if it is still misfiring, it is likely there is another issue from the flooding with the wiring harness and connectors and will be very hard to fix.
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