Forum Discussion
ShinerBock
Mar 05, 2017Explorer
blofgren wrote:
Wouldn't an indication of this be noticeably less fuel economy than the other trucks? Also I would think if that new of a truck was in regen that soon there must have been something wrong with it.
No, defueling a diesel does not give you less fuel economy. It will give you less power from the engine. Well, technically you will use more fuel because it takes you longer to get up a hill versus having full power, but seeing that all of these trucks were about the same time, it wouldn't have been noticeable in this test.
Most modern diesels are programmed to defuel if certain parameters are over their limits like EGTs or boost pressure. Another form of defueling is torque management where you do not get full engine power in the first few gears because the ECM programs it to inject less fuel until you get into the higher gears.
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