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Ok now I understand it a bit better. That's kind of weird because the various other Skunk2 TB equipped cars I've tuned did not have this problem.

Yeah I noticed idle advance was on too, I haven't needed to use it before so when I re-do your closed loop idle settings with the new numbers I'll disable it.

Stuck tb is a skunk2 thing. Seems a lot of the new ones have the issue. @curly fixed it with a new hole.

Edit: disregard, this is just to increase spring tension, got it.

Quote:

Originally Posted by psyber_0ptix (Post 1433666)

Edit: disregard, this is just to increase spring tension, got it.

So you got it sorted out?

Quote:

Originally Posted by psyber_0ptix (Post 1433610)

So the throttle itself, without adjusting the stop, wouldn't close on it's own completely unless there was momentum behind it closing. If I where lifting slowly and coasted, it would sit at 1% TPS and high idle. If I where to jab the throttle, it would close completely. I added a spring to help keep the throttle shut, but even that isn't helping out too much now. So just to try, I adjusted the stop to the point where it barely touched and adjusted the bypass screw in to help drop the high idle. After all is said and done, it idles at 1000 without any help of the bypass.

Trying to figure out the idle with this Skunk2 throttle has been an ongoing challenge. Working around it's deficiency getting "sticky" when closing or little adjustability thereafter, I'm not certain other than trying a heaver spring to keep the throttle shut. I want to replace the throttle stop screw at some point for longevity and easier adjustment than the oddball allen key I have to carry, will try to set things back and report in.

As of current idle valve test has a range between 3 and 55%, but I'm not sure if some of that fluctuation is just idle bouncing around few hundred rpm's and the fans kicking on and off.

Also, I don't know if I used advance at Idle before, but it's enabled when I got it back from PTuning. Should this be disabled during idle test?

sent VladiTune revision #3 :)

Quote:

Originally Posted by miataman04 (Post 1433767)

So you got it sorted out?

The idle, not yet. I don't have facility to remove the cam on the Skunk2 to redrill to tension the spring tighter. Will pursue this as best it can be until winter mode allows me to start tearing things off the car for funsies.

Quote:

Originally Posted by 18psi (Post 1433828)

sent VladiTune revision #3 :)

Received. Will work on it tomorrow, the only sunny day this week.

I've been meaning to ask: do you notice the boost oscillation on the boost gauge?

@18psi, I'm usually white knuckle gripping the wheel with my eyelids flapping around trying to not poop myself.

I'll check next time.

Boost gauge is connected via long vacuum hose, so it may be slightly damped compared to the inches of hose on the AEM Map sensor.

For testing purposes, should I enable and use the onboard MAP?

lol with that much power, I would be too.

with the way it's spiking though, you should still see the fluctuations on the gauge: it goes from 19-20 to 16 and back up, that's a pretty large swing.

I'm just trying to figure out if I should smooth/filter the signal from the map sensor because the signal is noisy, or keep pursuing this jigsaw boost issue.

The cable shielding is grounded near the throttle body near where the sensor itself is mounted. Do you suppose it's hitting some sort of resonance at high RPM for it to read funny in the pressure transducer? I can always try extending and relocating the sensor to somewhere with less vibration. I don't know if it's signal noise without zooming into the log, but it I'll check the boost gauge first.

yeah I'm starting to suspect resonance or turbulence or something. because your map signal is rock solid otherwise.

heck, I even suspected turbulence way back before we even started troubleshooting the wg arm. it's just so odd that it only happens up top

What if we used the onboard MAP since it's only pushing ~20 psi and use the AEM as barometric pressure. You think it'll show wild oscillation despite the slight under hood pressure changes? Purely for observation.

Moving the sensor is still a non issue and may be easier to try out without having to dig into settings. I'll see what I can do this week.

Whichever is easier for you to try (and then reverse if need be).
Just so we know if it's a legit

I just got this idea: dug up G's 6258 dyno plot.

look at the boost plot, look familiar?

https://cimg4.ibsrv.net/gimg/www.mia...d7c0c4b1b8.jpg

notice also that the one that jigsaw'd the most was the lowest boost setting. this is also on the internal RevMS3 map sensor.

So same symptoms, different map sensors. Could it be board electronics or the EBC frequency/PID?

G => RyanG?

Quote:

Originally Posted by psyber_0ptix (Post 1435328)

G => RyanG?

Not me. I never had a 6258....or a properly functioning car with an EFR :cry:

Quote:

Originally Posted by psyber_0ptix (Post 1435328)

So same symptoms, different map sensors. Could it be board electronics or the EBC frequency/PID?

G => RyanG?

Gordon aka EO2K

My guess is EBC frequency. He's also in open loop like you. Neither of you are running closed loop, so no PID

Ok, so currently boost settings are:

https://cimg4.ibsrv.net/gimg/www.mia...b96fafb648.png
https://cimg2.ibsrv.net/gimg/www.mia...053d6ae7be.pngPump93
https://cimg5.ibsrv.net/gimg/www.mia...90d396bd4a.pngE85

Would switching to mid frequency range at 30Hz help stabilize the oscillations at upper pressures? Would this require higher duty to reach the same targets since it's working marginally faster?

In my experience lower is betterer. Changing it more often makes it almost harder to tune.