ReStylin

iTrader: (1)

So it only happens sometimes.... and some gears...

I had someone change my haltech boost control setting to closed loop...

Ran perfect..... The other day it was 32 celicus out.... 75% humidity. and I overboosted to 25psi.
My haltech overboost cut is @ 20psi... at 30ms time. So I would overshoot 20psi by 5psi in 30ms.

had it changed it too 10ms, lowered duty cycle.

Yesterday in 5th gear, overboosted again 20 celcius, 88% humidity..... **** Haltech engine cut is harsh under full accl haha.

I checked all vacuum lines with smoke. All good.

Cux350z

iTrader: (162)

when you say "ran perfect? do you mean you tested the closed loop control and it worked and then now it doesnt?

Closed loop needs a good base duty and then the pid tuned

MR RIZK

iTrader: (7)

If all the PID and CLBD settings are ok try increasing the control start pressure or increasing the closed loop delay. If the delay is too short once the boost builds as per the CLBD table and hasn't had time to stabilize it may overshoot when correction kicks in. The default is 0.5 but mine is currently set to 1.7sec's

As Cux mentioned the base duty is important otherwise you will be chasing your tail. There is a few threads on here on how to tune the closed loop boost control.

That is what I noticed on my setup anyway

rcdash

iTrader: (18)

"someone" didn't tune it right. ^ u can find the appropriate base duty by doing some logs of duty cycle, boost, and speed. then set up a 2d map for base duty cycle.

binder

iTrader: (8)

I agree with above.

I just set open loop and do 0% duty cycle and see what my spring pressure is then I do a 10%, 15%, 20% and so forth to see what boost I'm getting. From there I use those duty cycles in closed loop mode. You didn't mention your system but if it spools really fast you might need to start the controller more like 5psi instead of the stock 3.5psi before threshold. Once you keep it from over shooting then you have to adjust those PID settings to get it to stabilize.