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Old Sep 14th, 2017, 17:15   #14
SwissXC90
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Last Online: Mar 20th, 2024 18:26
Join Date: Jan 2016
Location: Cross Country
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Quote:
Originally Posted by poiuytre111 View Post
I once had a BMW diesel with wildly optimistic mpg readings that had been given a fairly crude remap - primarily an increase in fuel rail pressure. I always assumed the two things were linked - has your car been remapped perhaps ?
Shouldn't be

The engine control unit opens the injectors for xx microseconds

Given known fuel rail pressure and injector size and injector opening time, the amount of fuel used can be measured exactly. Regardless of remap.

Combine exact fuel usage with exact distance travelled and you can calculate the MPG (or km/100L)

I think it may be more a sampling size issue

At any rate, it is entirely software driven and no adjustment is possible....
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