osso Posted October 21, 2003 Share Posted October 21, 2003 I had a look this lunch time at all the pipes going to both the IACV VSV and the IACV actuator, i also checked the all the pipes going to both the EGCV VSV and the EGCV actuator, and everything seems fine.. now where the heck is the pressure tank? i couldnt see it from the top of the engine bay.. i understand its under the manifold? has anyone got a pic handy to show me the location of the pressure tank? i am assuming i would need to follow the IACV pipes which would lead me to the pressure tank, is this correct? whats the best way to access the pressure tank? can it be seen easily from underneath the car? Please correct me if im wrong, but i am assuming that the pressure tank is used to build up the pressure to open up the EGCV actuator, after all it's alot bigger than the IACV actuator! Is it true that the TTC mod would bypass the pressure tank? if so it might be easier doing the 30 minute conversion without jacking the supra up.. cuz i am now thinking there's a problem with either a loose hose under neath the car which connects to the tank or the tank itself is leaking badly... what do you lot think? Cheers James Link to comment Share on other sites More sharing options...
osso Posted October 21, 2003 Author Share Posted October 21, 2003 Just had a quick play around in the engine and the IACV Actuator is closed in idle, and when you rev the engine to around 4k rpm, the Actuator opens up, you can actually see this operate when the engine is idle, which suggest to me that both the IACV Actuator and the IACV VSV are both working, and the air flow pressure to the IACV Actuator and VSV is fine.. However the EGCV Actuator doesnt open up, whether it opens when the engine is in idle or under load I wouldn't know.. actually, I don't think it would, because it relies on the manifold pressure to open up the EGCV Actuator! I wonder if the EGCV VSV is working.. does anyone know of a way to test the EGCV VSV solenoid? Wish I had a bicycle pump handy to test the Actuator.. I am getting there I suppose.. just hope I can get it fixed before Thor's dyno day on Saturday! Cheers James Link to comment Share on other sites More sharing options...
dude Posted October 21, 2003 Share Posted October 21, 2003 Now going to this so can have a peak while there. dude:flame Dev Link to comment Share on other sites More sharing options...
osso Posted October 21, 2003 Author Share Posted October 21, 2003 Nice one, what i'll do before Saturday is test the EGCV Actuator with a bike pump and check if that works and doesnt leak, then put the Supra TTC mode rather than Sequential which will bypass the EGCV VSV and the IACV VSV if the 2nd Turbo comes on in TTC mode and maintains high boost then it has to be a fault with the EGCV VSV! if it is the EGCV VSV thats faulty i doubt i will be able to get a replacement in time for the dyno day. Link to comment Share on other sites More sharing options...
osso Posted October 21, 2003 Author Share Posted October 21, 2003 Actually instead of putting the supra in True Twin mode, i'll just disconnect the Hose on the EGCV Actuator and see if it vents to air, it'd be quicker!! if it doesnt then thats where the problem is, surely? No point putting it in TTC mode since i know the IACV VSV is working! Link to comment Share on other sites More sharing options...
dude Posted October 22, 2003 Share Posted October 22, 2003 Of course the problem could be electrical !!!!!!!!!!!!!! Dude:flame Dev Link to comment Share on other sites More sharing options...
Matt Harwood Posted October 22, 2003 Share Posted October 22, 2003 You could try the ETTC mod... This would rule out electrical and VSV's... http://www.mkiv.com/techarticles/ettc/index.html Does the boost completely drop off at 4000rpm, or does it continue to boost at about 0.6 bar on turbo 1 ? Link to comment Share on other sites More sharing options...
osso Posted October 22, 2003 Author Share Posted October 22, 2003 Unfortunately i dont have a mechanical aftermarket boost gauge at the moment that i can quickly hook up, but what i can say that the Supra stops pulling and feels like an NA at 4k rpm which suggests to me that there is no boost driving Turbo #1 beyond 4k rpm for some reason it sounds like the main valve controlling the boost for the overall system is releasing the boost at 4k rpm.. would that make any sense? Link to comment Share on other sites More sharing options...
Ian C Posted October 22, 2003 Share Posted October 22, 2003 Sounds like the EGCV not opening. As turbo 2 hasn't got anything spinning it up, turbo 1's boost takes the path of least resistance which is straight through turbo 2, backwards, and out to the air filter. Where it gets sucked back into #1 again. Car ends up feeling a tad underpowered You can trap a bit of tinfoil between the EGCV actuator cam and it's screwstop, and go for a hoon. If the tinfoil has gone, it's opening at least partially. If it's still there and you went over 4000rpm, it's not opening... -Ian Link to comment Share on other sites More sharing options...
osso Posted October 22, 2003 Author Share Posted October 22, 2003 Well I have now put the car in TTC mode and both turbo's are not coming on at all! When the Supra was in Sequential mode the first turbo would boost, and the second turbo wouldnt start and all the boost would escape stopping both turbos Now in TTC mode neither turbo will boost! and it feels probably worst than a NA there is no power at all but still runs smoothly does that make any sense at all? When i took the big Air intake hose off to get at the pipes to the EGCV valve and VSV there isnt any sign of oil! which is a good sign. So whats going on? possible leak near the pressure tank under the manifold? Link to comment Share on other sites More sharing options...
osso Posted October 22, 2003 Author Share Posted October 22, 2003 Here's the latest, the Supra is now back in sequential and the First turbo is working again! Now i am back to square one, with the second turbo not spooling up! Before i reconnected the Inlet pressure to the EGCV VSV which comes directly from the "Pressure Surge Tank" i tried to blow in it, and it wouldnt give and it felt like it was blocked, which is what you would expect.. and if i blow hard into the pipe and fold the pipe so that it traps the air, then release the pipe, it hisses, so all the pipes to the pressure tank sound like they are ok.. So now im thinking the EGCV Actuator is leaking badly because the Pressure Tank has now manage to regenerate enough pressure to activate IAVC Actuator in sequential mode again. But it couldnt activate the IAVC Actuator while the pressure line was fed directly to both the IAVC Actuator and the EGCV Actuator (from the same line) Since the EGCV Actuator might be leaking, and when the Supra was in TTC configuration all the pressure which would have opened up the IAVC actuator escaped from the EGCV Actuator instead. What do ya think? Link to comment Share on other sites More sharing options...
osso Posted October 23, 2003 Author Share Posted October 23, 2003 I got a pump today and Checked the EGCV Actuator and the IACV Acturator and they are both ok, the rod extends and stay extended until the pressure is removed! I have managed to find the pressure tank, and i can feel the 2 pipes that connect to the pressure tank, and they are not loose! I also took off both Air intake hose and the intercooler hose which goes into the intercooler and there is no sign of oil anywhere... However i had a look at the radiator cap, and it kinda looked like water, and the cap it self had some brownish deposits on it.. i then had a look at the radiator filler hole and its extremely low and looks like there's water at the bottom? I thought this stuff was supposed to be a reddish ribena colour? surely this is where the coolant goes? could the ECU be cutting the power to both turbos because the coollant is low? I've not noticed any engine warning lights while traveling Link to comment Share on other sites More sharing options...
dude Posted October 23, 2003 Share Posted October 23, 2003 Have you tested the vsv's electrically ?????? Dude:flame Dev Link to comment Share on other sites More sharing options...
osso Posted October 23, 2003 Author Share Posted October 23, 2003 Hi dude, nope i've not tried to test the VSV's yet, im not entirely sure how to go about doing this.. Are 2 VSV's supposed to let air out when closed, and the other 2 VSV's supposed to stop air getting out when closed? if this is the case i suspect that the 2 VSV's which stop air when closed are the IACV VSV and the EGCV.. When i converted the Supra into TTC mode, that would have bypassed the IACV VSV and the EGCV VSV, and when the Supra is in TTC mode then the Bypass valve isnt needed which would mean the EBV VSV would be bypassed, however neither turbos would boost in TTC Mode i didnt feel the big pull at 4200 revs infact i didnt feel any pull, it drove like an N/A Supra.. which is really weird, surely the turbo's are on all the time? for some reason they werent generating any boost I am beginning to think that the reason why the TTC mode didnt work was because the pressure tank couldnt build enough pressure to open up the EGCV and the IACV actuators.. Link to comment Share on other sites More sharing options...
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