Once you have changed any electronic componants , the fault codes should be cleared. If the car has an EECV Ford PCM, you will have to drive it a little for the management system to 'learn' the new adaptive learning program in the PCM.
These Ford PCMs have a non volitile memory, so that even if you didconnected the battery cable the code would still be stored in the memory. You would have to use test equipent for this or a generic code checker.
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