**Fuel cuts in log visible on pulls starting at rows 1650 & 2700.**
I got a couple hard cuts earlier, while not logging, just driving.
Logged later after restoring stock overrun settings, and LDRXN reduced 185 until 5,500 where it's raised to 190 to redline. You can see from the file attached that actual lambda tracks specified pretty well although not with great precision. Why is it so jumpy? Poor HP fueling calibration?
Looking at the parts of the log with high load / injection times, it becomes apparent that the car is getting serious fuel cuts upper 4,000 RPM range. I have not had any HARD fuel cuts whatsoever while tuning this car up until earlier today. Yesterday I replaced my fuel filter and then logged the car for about 30 or 45 minutes on the road that but didn't experience any hard fuel cuts.
HPFP settings:
Rail pressures, limiter: 129 bar currently (RS4 relief valve)
VHDP: 377 (50% over stock,but is it correct for 9.8mm piston?)
RQUAHDPK: 24 mm^2 (my IE HPFP is 9.8mm piston, not 9.5 like APR pump. How to check the value for 9.8mm piston?)
I'm a little confused about calculating RQUAHDPK and consequently VHDP because a 9.8mm diameter piston does not have an area even close to 24mm^2, a value 50% over stock and probably close for this calibration if not exact.
Also, nowhere in the LAMFA or BTS do I specify an AFR richer than .8, however, in the log the ecu is seen to REQUEST AFR in the .7s.
Is it possible my LPFP / LPFP controller is a problem here, and unable to keep up at higher flows? I was tapping out 5th gear on a regular basis before today without having hard fuel cuts, just load pulled into the 150s by redline.
Your HPFP calibrations are correct:
RQUAHDPK = Piston radius ^2 or square of RQUAHDPK == piston radius >> 24.01 for Autotech HPFP (9.8mm piston)
You should make it slightly leaner, around 0.83 would be optimal.
Even with Autotech you will fall short of fuel below 5krpm.
I also suggest that you request the maximum rail pressure from 4000rpm and lower below that (e.g. 5 bars).
With those loads your LPFP shouldn´t be a problem.
With 330hp my stock LPFP has 77% duty.
