Eddie320
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I know. My point is, it used read accurate. And now this. How does it measure?Miles driven/gallons used.
Its obviously off, but the above equation will tell you by how much.
I will keep checking it by hand and see off I am consistently off by the same percentage. Again, how the hell does it measure? LolMy lie o meter is consistently off by 20 percent. So when I get 18 mpg hand Calc The lie o meter reads 18×1.2 or 21.6. I've been able to get 21 before on a long road trip though.
Pulse width is how it's calculated.I have no idea, you'd think it would just calculate the flow by pulse width and rail pressure and that would be pretty accurate, but I've heard they use maf, boost and all sorts of other sensors.
Tuners modify the software to trick the PCM into thinking the injectors have less flow than they really do. This makes the PCM open the injectors for a longer pulsewidth, so you get more fuel. The equation that the trip computer uses now also thinks you have smaller injectors, so it's fuel used calculation is off by however much the tuner modified it.But it was darn close to right on, before I tuned and deleted
Thanks!! Good info.Pulse width is how it's calculated.
Tuners modify the software to trick the PCM into thinking the injectors have less flow than they really do. This makes the PCM open the injectors for a longer pulsewidth, so you get more fuel. The equation that the trip computer uses now also thinks you have smaller injectors, so it's fuel used calculation is off by however much the tuner modified it.