Car is running
http://www.youtube.com/watch?v=TEZqa2bcTDo
but so far i have 3 firmware related problem.
1. While cranking injection angle is 720deg, not the value in table. So for direct injection it's big problem. I set that parameter to 720deg and rotate to wrong position injector outputs so i can start the engine.
2. PWM frequency of DBW(drive by wire) is 488.28Hz what is to low. DBW is louder than engine at idle. At stock car that frequency is 8kHz what is TCCR0|=0x05
- Good starting PWM frequency is 5Khz. (GunnarReynisson)**
3. When DBW is enabled, treshold for idle should be pedal(pps or throttle target), not TPS.
- Absolutely accurate (GunnarReynisson)**
Both requests have been implemented, selectable TPS/PPS1 threshold for IAC activation and selectable PWM frequency. Will be available shortly (watch firmware changes and run update files manually in VemsTune) - DB
I'm working on car with TFSI engine. 2.0 16v engine , 60-2 with camsyc(4 pulses, 3 can be filtered), variable cam ... and FSI injectors(spraying direct inside combustion camber at high pressure).
So problem is that engine has only 3-30bar(pressure depending on revs and how long do you crank and how long is engine turned of...) of pressure of fuel during cranking. Normal working pressure is 120bar.
Also engine has pressure sensor(0-5V) so i need to change req_fuel(fueltrim) depending on that voltage(pressure). But current scale is only 178% more, but i need a least 800% more.
Hello Damir,
Nice implementation on the direct injectors, to scale cranking pulse width a lot more use Anytrim in (crank_pw) mode this allows upto 697% scaling. Also a combination of Anytrims can produce a much higher percentage.
Required factor scaling from pressure alone: sqrt(120/3) = 6.32 (not taking fuel temp into account) should be quite doable. - DB
Help and details: http://vems.hu/vt/help/v3/v3_anytrim_control.html
.. Problem is that after cranking(so more than 400rpm) fuel pressure isn't 120 bar. It takes few seconds to reach 120 bar. So changing only crank pulses isn't enough. Better way is change scale of fueltrim.
And injectors request 80V for opening, but i solved that. Here is trace at wot(0.1bar of boost) at 1500rpm.
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