T2 MSW Posted April 16, 2015 Share Posted April 16, 2015 (edited) Ill try and make this as simple as possible I need to understand two things. My wastegates have 2 ports - Boost ref port which is what would open the wastegate when spring pressure is attained & control port which you would use to force the gate closed again to up the boost. I don’t think the wastegates are operating correctly on my car. I need to spend some time looking at it but heres what I suspect and I just need confirmation this could happen and my thinking is correct. Basically I have found a wastegate control pipe thats blown off and i suspect its always been like this and was mapped like this. Reason I think this is as soon as you put it on with 0.5 bar of boost it pops off again, no way it took 1.9 bar without coming off. What i need to know is below. 1) If this is the boost reference (i need to trace it and work it all out) to the control valve could the valve be loading the pressure on the alternate port of the wastegate now the reference port has been reconnected and secured on? hence why my wastegates don’t appear to open at all. basically the control ports which would be used to up the boost have been setup from atmospheric and the boost reference to the wastegates (of the turbo) is perfectly fine. To test this theory if I disconnect the reference ports where the boost control valve go to on the wastegates i should only ever be able to generate 1.1 bar, correct?? 2) Would the boost reference on the dash2 be in Kpa and actually the reading from the map sensor?? so its intake pressure? therefore when I’m seeing boost spikes of 250 its actually 2.5 bar?? Cheers Mike Edited April 16, 2015 by T2 MSW (see edit history) Quote Link to comment Share on other sites More sharing options...
mellonman Posted April 16, 2015 Share Posted April 16, 2015 (edited) There is a few ways in which external wastegates opperate , so could depend on your setup If you connect both lines to top and bottom of your wategate straight from the turbo then it wont open as you have the same amount of force holding it closed as trying to open , ( this could also be the same if your boost valve had jammed or not on correct N/C N/O port) the top of the wastegate is normally used for the control valve to bleed away the resistance holding the wastegate closed , which gives more control. using the N/C port of your control valve when both refences are used you can have it fitted to just the bottom of the wastegate which just pushes open at spring rate or fitting the boost control valve using N/O port . if you are just using turbo ref it needs to be fiited to the bottom so it can push against the spring if its just fitted to the top it will just add to the force trying to keep it closed , hope that makes sence maybe the reason for it blowing off could be if the diaphram has a split in the wastegate and is leaking through in to top chamber thus poping it off and giving you over boost and leak at the same time ? Edited April 16, 2015 by mellonman (see edit history) Quote Link to comment Share on other sites More sharing options...
T2 MSW Posted April 16, 2015 Author Share Posted April 16, 2015 Been looking at this tonight. Understand your explanation and I've got lower chambers as turbo reference. Top as control valve. Disconnect the turbo reference from the solenoid (which is the pipe that keeps blowing off) and the car hold boost at 1.1 bar but is mega laggy Connect pipe and secure it (as it simply slides off with ease) car over boosts to 2 bar and the ECU fuel cuts. No lag just too much boost. Take the solenoid out of the equation so the top ports vent to atmosphere and car holds 1.1 bar of boost and no lag. Could be solonoid is stuck open and both sides of the wastegate are getting same pressure. I can test this with the output test of the syvecs. Doubt it would be a damaged wastegate as they are brand new but never know so could be worth checking. Quote Link to comment Share on other sites More sharing options...
mellonman Posted April 17, 2015 Share Posted April 17, 2015 Mike could be solenoid . another test you could do is cap the top feed vacuum pipe with a bolt or something ( remember it might fly out if theres an issue ) and still see if its "mega laggy" or even use a longer peace of vacuum to run in the cabin to see / hear if air is leaking out of it. but this is similar to the venting to atmosphere . what wastegate spring do you have ? 1.1 ? you could also check the solenoid by giving it a direct voltage with some wire from the battery to see if you can here it click. a thing thats got me confused is how did you have boost control before if you say its alwasy been like this ? if thats correct then the control valve must have been on the bottom feed using the N/O port as i posted earlier , if you have now switched it to the correct set up with the control valve on top you need to change to the N/C port other wise it will bleed when trying to make boost and when boosting trying to keep the gate closed . this can be switched / flipped in the syvecs im sure Quote Link to comment Share on other sites More sharing options...
T2 MSW Posted April 17, 2015 Author Share Posted April 17, 2015 Capped the solenoid with a bolt last night to test that and it doesn't fly off when car holds 1.1 bar (wastegate spring pressure). Car also on full boost by 4K. Ill test solonoid later as that can be done with the output test on the Syvecs. Thats what got be confused too as on the dyno it had boost control to 1.1, 1.7 & 1.9 and the ports used have not been changed they are the correct way round and always have been. Only thing thats changed is connect the pipe that keeps popping off and secure it. Quote Link to comment Share on other sites More sharing options...
mellonman Posted April 17, 2015 Share Posted April 17, 2015 What im tempted to say then is f*^k it its working , If its not broken dont try to fix it Or start again from scratch making sure correct ports are used and is switch correctly in the syvecs its been a while since i have been messing with the boost solenoids so i may have the N/O and N/C the wrong way around Quote Link to comment Share on other sites More sharing options...
T2 MSW Posted April 17, 2015 Author Share Posted April 17, 2015 Its not working though, With the pipe disconnected (open line from the turbo i.e boost leak) it sort of works and the boost levels are correct and boost is held at the levels as above. but its working overtime as it has a boost leak. Put pipe back on and secure - 2 bar of boost. I need to find out from Mapper what controls the boost on the lowest Cal as i expect its the wastegate spring and its looking more likely its not its the solenoid. Therefore the wastegate control needs resetting up through the syvecs. Quote Link to comment Share on other sites More sharing options...
mellonman Posted April 17, 2015 Share Posted April 17, 2015 Sorry my mistake . re read it all, Solenoid looks to be not operating when pumped correctly , could be :- the solenoid vac pipe split syvecs boost ref so not telling the solenoid to work. try installing the solenoid in line with the turbo ref to the bootm and see if you have any control then , if its still leaking then its got to be the solenoid then just run wastegate boost until new one arrives Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 17, 2015 Share Posted April 17, 2015 Motec used to have an excellent video on wastegate control on the webinar section of their web site. Quote Link to comment Share on other sites More sharing options...
T2 MSW Posted April 19, 2015 Author Share Posted April 19, 2015 Cheers Chris, I'll have a look for that Quote Link to comment Share on other sites More sharing options...
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