Boost Controller going crazy

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CalMac
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Boost Controller going crazy

Post by CalMac »

Rev 3 turbo, standard turbo as far as I know with a Berk DP. Running Blitz Dual SBC. Also been running BOV-less for 6 months if that could affect the following:

Recently started hitting boost cut/fuel cut/some sort of wall at 1.15 bar on the Blitz readout. Obviously this is irritating as it keeps hesitating under acceleration so I figured that if I just lower the gain a little bit then I'll be running less boost and all will be well. It's worked great like this for months, having to occasionally adjust on colder days or when the conditions are damp but all in all pretty reliable method of maintaining a consistent boost pressure.

The last couple of weeks I've had to keep reducing the gain as it seems to be hitting this 1.15 bar wall quite often. It used to run fine with the gain set at 60 but now I'm down at 54 and it's still flashing red, beeping and limiting power when on full boost.

Is this likely to be a vacuum leak? Could it be clutch slip? Or something more serious like the turbo disintegrating? Sorry if the description is a bit vague - haven't really had issues in the last few years of ownership and so I've just left everything as it was and kept up with basic maintenance, avoided messing with any of the stuff I don't understand :lol:
raptor95GTS
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Re: Boost Controller going crazy

Post by raptor95GTS »

I have a similar EBC so I can check what settings I have tomorrow when I'm in the car. The Gain setting on the controller only changes how quickly boost rises to the preset limit. That limit is set by the Ratio so to lower your boost, lower the Ratio. Lowering the Gain would prevent overboosting on initial WOT. That at least is my understanding of how it works :)
CalMac
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Re: Boost Controller going crazy

Post by CalMac »

So I've been going about it the wrong way all this time? Doesn't surprise me :lol:

By pressing the right hand button I can cycle through three displays - current mani pressure, max recorded boost (of journey?), and gain adjustment. The left hand button seems to allow you to cycle through different preset gain parameters for high or low boost. Not sure if I can adjust anything else?
raptor95GTS
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Re: Boost Controller going crazy

Post by raptor95GTS »

does it look like below as it sounds like we have the same unit
Image

if I adjust the mode dial it allows me to cycle through 4 boost levels though I only have 2 set up. The Gain is set for the unit so it's the same for any Ratio (boost level) setting. I'll try and remember tomorrow to look at the settings and take a note of them. The high boost level is max recorded by the unit so not a journey figure, at least I dont think it is.
androo007
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Re: Boost Controller going crazy

Post by androo007 »

First things always mate check all lines running from solenoid through the system. A split on the actuator line could cause raised boost potentially. Start at one end and trace through. If you have to remove each at a time, blow for leaks and reattach with new clips.
raptor95GTS
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Re: Boost Controller going crazy

Post by raptor95GTS »

as said above check the pipes for leaks as that'll cause no end of issues. You can loop the solenoid pipes into each other which will give you actuator pressure around 10psi though I think I get 9psi on my gauge.
OK settings for mine,
boost 1 - ratio 34 - roughly 13psi
boost 2 - ratio 55 - roughly 17psi

Gain is 44
jimGTS
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Re: Boost Controller going crazy

Post by jimGTS »

The only way to access gain is to hold on the mode button for 3 seconds.

As mentioned above it sounds like you are adjusting the ratio/set value. Not the gain.

If flashing red you are clearly hitting the boost controllers limiter.

If you want to reduce how quick the turbo spools up to avoid boost spikes, you need to lower the gain.

Gain is likely to be set anything from 5-20 I'd guess.
On my 20b I had it around the 15 area. On the td06, strangely if works better at low figures, literally at 5-7.

The set/ratio should be anything from 40-60.
Last edited by jimGTS on Sun Apr 16, 2017 6:57 am, edited 1 time in total.
jimGTS
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Re: Boost Controller going crazy

Post by jimGTS »

I'd also look to doing an ecu reset.
If it's sensed knock at any point, I've found redued timing and higher than normal boost levels.
CalMac
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Re: Boost Controller going crazy

Post by CalMac »

Yep that's what mine looks like, will have a mess around when it stops raining!

Thanks for your settings guys, should help. I'm just dreading sifting through the engine bay looking for leaks :lol: Will it just be vac lines causing the issue or could loose intercooler pipework be responsible too?
raptor95GTS
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Re: Boost Controller going crazy

Post by raptor95GTS »

any boost / vacuum pipe could be causing the issue so best to check them all :thumleft:
chrismit
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Re: Boost Controller going crazy

Post by chrismit »

If its overboosting chances are it will be your vacuum lines. tear in a vacuum line going to the wastegate is like a free uncontrolled bleed valve..

If your setup has been running fine for so long then I doubt it would be the other parts listed, I initially ran into boost creep issues when I installed my 3 inch exhaust system and new DP but that was something that was noticeable right away (not after time slowly)

Less likely to be your boost pipes as they would just lose boost and your spool time would be increased / and you would have less boost in general.
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