Hello everyone.I am driving a 2001 Hyundai Accent (G4EA engine) with 280,000 happy km on it . The car as you all might know, has no trip computer, so I decided, with some help of course, to build my own, using Arduino.

The basic idea, is to count the pulses of the VSS sensor, so I can get speed values, and the Injector pulses (doesn't matter which one of the four) to get the fuel flow values.The code is almost complete- internet is an amazing place if you know what to search for- but I still require some help to make this project work.

Finding the injector flow specs was kinda easy, but I have no idea if the value I got is correct . I searched using the original manufacturer code so If someone can confirm it I would be grateful. The value I have is 118gr/min n-Heptane @ 3 bar, which can easily be converted to 172,51 cc/min(using metric here-sorry-).

Also, I would love to know the number of pulses that the VSS or speed sensor produces for every km or mile. That would help a lot, because although it's not hard to calculate that value, it will not be as accurate as knowing the pulse number. (My car has a cable driven speedo, that goes behind the dashboard, I 've seen it when I replaced the lighting on it.)

I need to read those values, which is the most difficult part for me, due to lack of experience regarding ECUs. I have the wiring diagram for the hyundai gets with the same engine type, which I assume that they are the same as mine. I know the location of the ECU (drivers side, next to the clutch) I can't unplug the main plug from it (already cut my finger, had to go to the ER for stitches) ... Any help with that?
Best regards,
Costas
P.S. sorry for the long post and my bad english