Stft

[n54boostn]

Anyone know what can cause the stft to drop to 0% during wot?

To remedy this issue. I’ve just replaced the hpfp, hpfp sensor, pre o2 sensors, crank position sensor, #6 injector and spark plug regapped to .20

datazap.me | N54x | Log 1592118911

datazap.me

 

[JohnDaviz]

i have a similar issue with stft flatlining. In my case it seems to go along with misfire above 6k rpm.
My misfire issue is pretty weird as the CEL is not going on steadily but it was only blinking and gone when i went off throttle. After reading error codes i had misfire as active codes without CEL on.
I read somewhere that with a misfire fuel trimming goes flat.

 

[iminhell1]

Not enough data.


Almost looks like it could be a PID priority issue. One coming in slower than another (STFT fast and Throttle slow). That makes it look like something is going on that isn't.
But like I said, not enough data to make any real call here.

 

[n54boostn]

Not enough data.


Almost looks like it could be a PID priority issue. One coming in slower than another (STFT fast and Throttle slow). That makes it look like something is going on that isn't.
But like I said, not enough data to make any real call here.

Thanks for the reply. Here the log

datazap.me | N54x | Log 1592118911

datazap.me

 

[iminhell1]

I think you have a bad injector. One on Bank 2 by the looks of it.
Something with the HPFP is going on. Pressure falls a lot but jumps back quickly. Can happen because an injector hangs open or closed, depends on what pressure is commanded (is it the high or the low?).

I think the 0 STFT is from the HPFP/injectors being uncontrolled.
It's like virtually every log of mine and others I've seen .... right around that 4,000 RPM mark shit starts falling apart.