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myburb
07-11-2015, 04:47 AM
I normally don't get to run on the freeway so don't get a chance to see blm's under changing conditions. On average my blm's run 130-132 and the wideband cycles around 14.7 so wasn't going to do anything with ve until I am burning another chip. My intake is an edelbrock tbi and I am running no hot water and my pcm is using water temp only for temp. Going on my run in the morning with 70 oat blm's ran 130-132. Coming home oat was 85 and blm's were 138-140 and water temp was up by 2-3 degrees. My thought was with ecm temp predicated on water temp that squirting the same amount of fuel with thinner air would have made it run richer. Do you think the 2-3 water temp could have changed the equation that much. Any how, opinions?

ony
07-11-2015, 06:39 AM
mybe one way the wind was pushing you or down grade road and the opisite going the other direction.

1project2many
07-11-2015, 01:38 PM
Yes, there are a number of reasons I'd expect to see lower BLM with higher engine temperature. Decreased oil viscosity reduces engine and gearbox load. Increased air and fuel temperature promotes faster, more complete combustion. But there are plenty of variables that can caused increased BLM. One is the ecm's inability to update barometric pressure if you never go to high throttle / no vacuum conditions. Fuel is another. And as ony suggested, actual load on the engine including wind resistance and elevation change.