Boost vs. WGFV DC and DC vs. Temperature

[Wallace White]

Larry -

Your duty cycle observations fit with what I've seen, in my limited
observation. I haven't seen more than 50% duty, even with my QLCC 1.8
bar chip. At colder temperatures the peak duty is lower.

But those peak DC values were very brief, just right when I first hit
WOT. Then the pressure rises quickly and the DC decreases. It's like a
servo-controlled motor system, where the controller uses PWM
proportional to the distance from the target.

Maybe your WGFV is partially blocked? Then it can't do quite as much
good as it should?

Wait a second, you should be getting 1.2 bar (or 1.1 indicated at least)
without the WGFV cycling at all. (Or is that affected by ambient
pressure?) What pressure do you get if you electrically disconnect the
WGFV?

- Wallace
  '87 5kcstq 172k

> Something that threw me for a loop was an extreme ambient temperature
> dependence on maximum DC.  I find my DC changes with ambient temperature
> approximately hitting the following points: <40F=<10%, 50F=25%, 55F=30%,
> 60F=40% and >65F=50%.  Boost follows that predicted by duty cycle.   This
> doesn't seem right but I haven't identified what is causing it.  It
> definitely reduces my boost in the winter.  Maybe I need to move to Florida.