It was late last night and my thinking cap was aleready in bed. The code reader is picking up codes, like it should, but the codes have not repeated enough to turn the CEL on.

When a MAP really fails, you will run slightly richer unless you are at altitude and this could cause the front O2 sensor to read rich. Many times, both of these conditions go away and resolve themselves.

Klaus
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There is no present time, just the past and future