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It's running stoichiometric and pumping losses have been reduced...the problem is the airflow required to maintain speed has gone up. The discrepancy is pretty small, 0.27 vs 0.29 load, which may have more to do with air temp than anything else.
The thing is, the engine's efficiency should NOT be this sensitive to adding 2% more EGR, so I want to say it has to be the ambient temperature and fluid temperature, but it is difficult to explain how the fuel economy dropped after adding EGR. Even if you are adding EGR past the point of diminishing returns and not adding timing, the fuel economy loss from 2% more EGR would be closer to 2% than 5 or 10%.
The correct thing to do of course is flash my old map back and test the car on the same stretch of road at night when air temperature is stable, but I still think something is wrong.
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