[wagonman76]

Something I was thinking about last night as it poured rain all the way from downstate to home, and I was getting record mileage with the 6000 wagon.

I know that very small changes in the map sensor have a big effect on fuel use. I used a map sensor modifier in the Celeb, and when turning it down just a little, it would cut out when touching the gas. But I did find one spot about 100-150 mv lower than stock where it seemed to give a hint more power under light load. So I left it there. I dont know if it contributes to my mpg gains or not. At the time I didnt notice any better or worse mileage but I was also not hypermiling yet either and I was getting a measly 32 mpg downstate and back consistently. Right now the car is under 2 feet of snow so it wont be experimented with till probably May.

The map sensor is manifold absolute pressure. I was wondering if it might actually measure the differential between manifold vacuum and atmospheric pressure. If so, then I was wondering if changes in atmospheric pressure could throw the map sensor off a bit, possibly in our favor. I believe a barometer measures atmospheric pressure and rain is way on one end of the scale.

Any thoughts?