BPV releasing pressure at mid boost, but im not letting off...

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2008 Mazdaspeed3 Grand Touring - Black Mica
Been having this issue lately, when I'm WOT I hold boost fine and it runs as normal but now under partial boost/throttle my valve has been releasing pressure prematurely when I'm still on the throttle...

latest things I've installed were a GReddy Profec B-spec II EBC and had a Cobb Protune on my AP with the EBC.
 
My guess is that it's the EBC and your AP tune not playing well with each other under light or partial throttle situations. You may need to go back to the stock solenoid boost control. First check to make sure you have the EBC properly plumbed. If it is installed correctly then:

I'd either disconnect the EBC and plumb the stock solenoid boost controller back in the system and retest, or maybe put the stock bpv back on and retest. Don't do both at the same time! You'll just get confused and then not know where the hell you are. One mod change at a time.
 
Yeah that's what I was thinking... I would hope the AP tune plays well with the EBC considering the guy who tuned the car does MS3's regularly and tunes the GReddy EBC's all day anyway. I'll get in touch with him to see what the map boost targets are set at, I don't know how it works with the AP map if he was tuning the EBC and not using the set boost targets from the ECU.

I know it's definitely installed correctly, reinstalled the valve unit monday to a better location using reinforced hoses, made sure to follow the instructions to the letter again and I have it sourced directly to the stock BPV source from the intake mani for the best response. The BOV is now getting its signal from the brake booster line, installed a vacuum manifold in line with it for a few extra vacuum ports. Checked everything for leaks multiple times and haven't had any issues after the install there.

I'd have maybe thought that using the brake booster line is giving me the issue with the BOV but it was doing this before when I had the EBC and BOV tee'd to the same source, so my only guess is that it IS the EBC.

In which case from my other thread you were correct and I do apologize if I sounded patronizing at all with my reply.

Damn these smart ECU's not liking extra toys.
 
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What are the benefits of running an EBC with a tuning device such as the AP? Shouldn't the AP do that for you as well? I always thought people used boost controllers to up the power without having to spend big bucks on tuning devices.
 
It's apparently easier from the tuner's side to tune a standalone boost controller than to go and mess with the boost targets for the AP maps.

I think my problem may be that running 18-19psi on the EBC and having the start boost set at 16.6 psi is giving me my BOV release issue... I have the release issue when my dashhawk and EBC are reading 13-14psi and the start boost dictates when my wastegate opens under acceleration, it's supposed to be under WOT but... who knows, thats my most educated guess.
 
I would agree that it's probably the EBC not working with AP. One or the other of them is "seeing" what it thinks is a harmful condition or load limit based on the action of the other and opening the wastegate prematurely under light load, part throttle conditions.

I also agree that custom tune of the AP without the addition of the EBC is probably the way to go.

You might want to check over on that other board which includes "speed" in its name. There are many very hard core race oriented modders over there and a lot of dialogue with tuners there that does not show up here. There are probably threads there involving attempts to use EBC with tuning solutions. I seem to recall reading something there that suggested that EBC was going to be fail with AP. Maybe I'm wrong. I have never attempted to use MBC or EBC on this car, which is, as we know very tricky regarding mod compatility, anyway. The stock ECU is extremely controlling and the fuel management system is as complex as anything out there.
 
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Thanks for the input, I'll check out the other board and see if I can't get any help there.
 
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