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OBD1 8bit Fuel

Library.OBD1_8bitFuel · r1.1 · · guest

Given table value ''v'' and multiplier value ''m'', the fuel value as seen in a ROM editor is:

Fuel(''v'',''m'') = ''v*m''/4


The result is presumably proportional to the amount of fuel entering the engine. It has an effective range of 0-16256.25 -- so how does this relate to injector duty cycle?

Pulse width (ms) = PW = (''v*m''/4)/100 + 0.60ms = ''v*m''/400 + 0.60ms

Max Duty Cycle is (((1000*60*2/rpm)*0.9ms)

Duty Cycle = PW/TRPM = (''v*m''/400 + 0.60)/(60000/''RPM'')

Simplifying,

Duty Cycle = ''RPM''*(''v*m'' + 240)/24000000

This is based upon information provided by Didier Pelegri and not verified by myself.

--AndySloane