scottysupra Posted July 21, 2009 Share Posted July 21, 2009 Hi all. Ive recently fitted a pair of standard jap spec turbos to my supra due to the old ones smoking. Both turbos were boosting as they should and every thing was fine for a road test for around half an hour, then just as i was heading back i lost boost on the first turbo. It drives fine with no smoke or strange noises but just with no boost untill the second turbo cuts in. Any ideas where i should start looking??? Quote Link to comment Share on other sites More sharing options...
Steve Posted July 21, 2009 Share Posted July 21, 2009 Have you had a read of this http://www.mkivsupra.net/vbb/showthread.php?t=35926 Quote Link to comment Share on other sites More sharing options...
scottysupra Posted July 22, 2009 Author Share Posted July 22, 2009 Cheers thats a good guide. Looking at it it seems the IACV valve is stuck open. Does anyone know how to solve this problem? Ive checked all my vacumn hoses today and they all seem o.k. Quote Link to comment Share on other sites More sharing options...
Steve Posted July 22, 2009 Share Posted July 22, 2009 In this pic, 6 is the IACV valve and 7 is the VSV that controls that valve. You need to check the arm on the valve moves freely. It sits on top so is easy to get to. I would also test that VSV to make sure it actually opens. Quote Link to comment Share on other sites More sharing options...
scottysupra Posted July 23, 2009 Author Share Posted July 23, 2009 Excellent i will go and check that now, thanks. How will i know if the vsv works? Is it just a matter of trying another one? Quote Link to comment Share on other sites More sharing options...
Steve Posted July 23, 2009 Share Posted July 23, 2009 You can put 12volts on to it, you should be able to blow through it either when powered or not, not sure which way it works. Quote Link to comment Share on other sites More sharing options...
Guest christodav Posted July 26, 2009 Share Posted July 26, 2009 Greeting guys! Sorry this is my first post. I will post on the intro thread ASAP. I have exactly the same issue. However, I have checked the IACV as described and all seems well. i even opened up the valve to see if the butterfly was working. all good. Any other ideas? What do I check next? Chris Quote Link to comment Share on other sites More sharing options...
Guest christodav Posted July 28, 2009 Share Posted July 28, 2009 Anyone? Quote Link to comment Share on other sites More sharing options...
scottysupra Posted July 29, 2009 Author Share Posted July 29, 2009 Ive still not fixed mine yet i just havent had the time lately. Ive checked my IACV valve too and mine doesnt appear to be stuck. The next thing to try would be the vsv that operates it. Does anyone know if the actuator on the first turbo could cause it to lose boost??? Quote Link to comment Share on other sites More sharing options...
Guest christodav Posted August 9, 2009 Share Posted August 9, 2009 Knowbody else seems to think so, but I think it could be the wastegate. I replaced my front turbo only and used the wastegate that was attached to the the replacement. I might change it back to my old one and see what happens?!?! Chris Quote Link to comment Share on other sites More sharing options...
Guest christodav Posted August 17, 2009 Share Posted August 17, 2009 I think I have found the problem. The EBV is not working. The actuator that operates it seems to be functioning as it should. I pulled all the piping off the top of the system and removed the actuator. The valve does not sound like it is shutting when moving the EBV arm by hand. It feel loose and rattles. I will let you know how I go. Chris Quote Link to comment Share on other sites More sharing options...
pistonbroke Posted August 17, 2009 Share Posted August 17, 2009 You can eliminate the VSV's as being faulty (wouldn't be the first time, they are known to fail) by putting the car into TTC mode. Do a search on here or google, there's step by step 10 min instructions on how to do it. TTC mode will bypass the VSV's and have both turbos coming on at the same time. You'll have to have a boost gauge to see that you are seeing max boost. Quote Link to comment Share on other sites More sharing options...
Guest christodav Posted August 19, 2009 Share Posted August 19, 2009 I fixed it! It was the EBV. The actuator arm had come off which left the valve 'flapping in the wind'. The tiny 'e-clip' which holds the arm had come off at some stage during my turbo swap. A new clip and away it went! This is what I would recommend to test it. Remove the short vacuum hose that connects the metal pipe to the large 'y' air pipe. This is the one you can see on the top of your engine right up the front. If you trace the metal line, it goes all the way to the back and disappears back into the darkness near the firewall. Pop a bike hand pump onto this line and pressurize it. DO NOT PUMP MORE THAN 20 PSI!!! My pump has a gauge. Pump too much and you could damage the actuator. If you lean down and look underneath the IACV you will just see the EBV actuator and it's arm disappearing under the heat shield. You will find a flashligh handy here. If the arm moves with pressure and the pressure is held, you don't have any leaks in there and the actuator is fine. (When you remove the pump air will escape and the arm will move back.) If air escapes whilst it is getting pressure from the pump, then it is likely that the short hose at the back is split or the actuator is faulty. The only way to see if the arm is still connected to the valve is to remove most of the top piping, remove the heat shield and you will see. If you have exactly the same problem as me, good luck with popping an 'e-clip' back onto the arm!! I ended up using an oversize one and modifying it to fit. Good luck!!! Chris Quote Link to comment Share on other sites More sharing options...
pistonbroke Posted August 19, 2009 Share Posted August 19, 2009 Good effort mate Quote Link to comment Share on other sites More sharing options...
Guest christodav Posted August 19, 2009 Share Posted August 19, 2009 Good effort mate Thanks. Quote Link to comment Share on other sites More sharing options...
scottysupra Posted August 19, 2009 Author Share Posted August 19, 2009 Excellent mate well done in fixing it. I will have a go at sorting mine out this weekend and let you know how it goes. Quote Link to comment Share on other sites More sharing options...
scottysupra Posted August 23, 2009 Author Share Posted August 23, 2009 I fixed it! It was the EBV. The actuator arm had come off which left the valve 'flapping in the wind'. The tiny 'e-clip' which holds the arm had come off at some stage during my turbo swap. A new clip and away it went! This is what I would recommend to test it. Remove the short vacuum hose that connects the metal pipe to the large 'y' air pipe. This is the one you can see on the top of your engine right up the front. If you trace the metal line, it goes all the way to the back and disappears back into the darkness near the firewall. Pop a bike hand pump onto this line and pressurize it. DO NOT PUMP MORE THAN 20 PSI!!! My pump has a gauge. Pump too much and you could damage the actuator. If you lean down and look underneath the IACV you will just see the EBV actuator and it's arm disappearing under the heat shield. You will find a flashligh handy here. If the arm moves with pressure and the pressure is held, you don't have any leaks in there and the actuator is fine. (When you remove the pump air will escape and the arm will move back.) If air escapes whilst it is getting pressure from the pump, then it is likely that the short hose at the back is split or the actuator is faulty. The only way to see if the arm is still connected to the valve is to remove most of the top piping, remove the heat shield and you will see. If you have exactly the same problem as me, good luck with popping an 'e-clip' back onto the arm!! I ended up using an oversize one and modifying it to fit. Good luck!!! Chris Ive fixed it too!!! I had the exact same problem! The EBV valve arm clip had fallen off so the arm had come loose. Thanks for your help mate it would of been one of the last things i would of checked! And your right its a pain trying to get a clip back on! after a lot of struggling i managed it though! Thanks again!!! Quote Link to comment Share on other sites More sharing options...
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