S300 BBG overboost at random
I have Hondata S300 with boost by gear in a p06. I have the boost control set to run on the wastegate (10psi) in gears 1-2 and boost up to 17psi in gears 3-4. Solenoid is "normally open" and is set as so in s300. Most of the time it works properly but at random, sometimes it tries to boost a million psi and hits boost cut at 20psi (only happens in gears 1-2). So I let out, double check my settings then get back in it and boosts 10psi again. WTF? I have quick spool turned off, and tried "duty cycle by gear" as well as "psi by gear" with the same results. Has anyone run in to this before and what was the fix?
Well, obviously gears 1-2 have boost values set to 0. (sorry for not including that). I have not logged the issue but it seems as if the duty cycly is 100% at that point like the ecu forgot it is set to "normally closed, max boost at 100% duty" and inverted that setting to a "normally closed" position.
Well, obviously gears 1-2 have boost values set to 0. (sorry for not including that). I have not logged the issue but it seems as if the duty cycly is 100% at that point like the ecu forgot it is set to "normally closed, max boost at 100% duty" and inverted that setting to a "normally closed" position.
If your using a Hondata spec solenoid it should be set to normally closed.
Last edited by mtber; Dec 28, 2012 at 08:30 PM.
I tried a setting "close" to 0 using both "duty vs gear" and "target boost vs gear" with the same result. It's a Mack valve. Like I said, it seems as if the ecu switches the setting by itself at random from "normally open" to "normally closed"
You must not be doing something correctly or have a software issue.
Try un-installing smanager, installing the latest version from hondata.com and going from there.
x2, doesn't sound like you're installed correctly. Try bypassing the EBC and routing straight to your wastegate if you want to rule out any mechanical or vacuum issues first.
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The wastegate works perfectly on its own. Before I installed the boost components I was running the Mac valve to a MBC on an aux output set to 65mph. It worked perfectly. I something were installed wrong I don't think 3rd and 4th gear would boost correctly all the time. I'll try the uninstall and update thing.
i am very familiar with s300 and p06 ecu's. send me your basemap, installed components list, and engine type. i should be able to get ya goin real quickly. datalog would be great too get the bottom of it faster, but i dont need it if you dont have one handy. make one next time you are out for a joyride
Sorry, I don't have a log. I have not been driving the car cause it overheats now with a new radiator and new thermostat. I think this problem lifted the head just enough to wash the gasket or maybe crack a sleeve. IDK yet. I noticed too late that it boosted 22psi at 13.5:1 afr on pump gas. If someone can advise me how to post my s300 calibration I would appreciate it.
*Update* That evil ecu killed my sleeves. 5 small cracks in cyl 1,3,4. and looks like the sleeves had been wobling a bit. Got Dartons in the works right now and getting the head done up a bit. I'll be back for testing in a month or so.
One thing I did not see anyone mention(scrolled through quick incase I missed it) is how are you reading your speed? If you are reading your speed off the stock vss then I would guess your spinning now and then which is causing your ecu to think you are in a different gear causing the spike. Sounds like this to me as you are only having the problem in 1st and 2nd gear. Something to look at anyways when you get it all back together.
Man, sorry to hear about the carnage! It appears that your gears are monitored by vehicle speed. The speed sensor should have a grounded RFI shield to eliminate noise. That may have an effect.
You could install a manual boost controller as a back-up while you get the electronics worked out. If the electronics fail, the MBC kicks in and prevents another expensive experiment.
Mike
You could install a manual boost controller as a back-up while you get the electronics worked out. If the electronics fail, the MBC kicks in and prevents another expensive experiment.
Mike
Ok, new bottom and freshened up the head. Good as new but still saw the same eratic boost control issues. I replaced the whole ecu/s300 and shazam! Problem solved until tonight. Made wastegate pressure (10psi) in 1st/2nd, 14psi in 3rd and 18psi in 4th. Tried to raise it up a bit in gears 2/3 and my Smanager program froze up. Closed it out, reopened it and uploaded to the ecu and that same issue came back on this new ecu. I tried unplugging the ecu, changing settings ect.
I read something about a diode install to help with voltage spikes to the solenoid. Does anyone have experience with this?
I read something about a diode install to help with voltage spikes to the solenoid. Does anyone have experience with this?
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