DoDo1975 Posted May 2, 2018 Share Posted May 2, 2018 Hi, Smoke test has revealed a leak from the TGV adjacent to cylinder 3. There is a small seal/gasket on the shaft of the TGV. Do I need a new TGV or can I just replace the seal? Thanks, Link to comment Share on other sites More sharing options...
relative4 Posted May 2, 2018 Share Posted May 2, 2018 Do you mean TGV? Link to comment Share on other sites More sharing options...
DoDo1975 Posted May 2, 2018 Author Share Posted May 2, 2018 I might. I thought mechanic said Throttle Position Sensor, but maybe I was wrong? This is right above the cylinder where the intake meets the head and its definately on cylinder 3 Link to comment Share on other sites More sharing options...
Max Capacity Posted May 2, 2018 Share Posted May 2, 2018 Easy to replace, just a labor intensive job. I lifted each side of the intake to replace the old black o-rings with the new larger orange ones years ago. Another way may be to remove the coolant lines, fuels lines from the shock tower and lift the intake at the heads. Replace those gaskets too. http://people.csail.mit.edu/ilh/vacation/ Most dealer websites will have a Parts link to see all the parts. 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
relative4 Posted May 2, 2018 Share Posted May 2, 2018 The throttle position sensor is on the throttle body, center rear of the intake, more toward cylinder 4 than cylinder 3. Definitely not right above the cylinder where the intake meets the head. Max is referring to the intake manifold gaskets, which are a common source of leaks, but from the sound of it, not what your mechanic is referring to. The tumble generator valves are above the cylinders where the intake meets the head. The ends of the shafts, above cylinders 2 and 3, spring a leak, and it sounds like that's what your mechanic is referring to. This happens on '07-'09 LGTs; is that what you have? Filling out your profile will be very helpful. There is not a single straightforward fix for this problem, but various people have successfully fixed it with various different techniques. When fixing the leak above cylinder 3, it will be advisable to proactively address cylinder 2 as well. This will help you get started: https://www.google.com/search?q=tgv+shaft+seal+site%3Alegacygt.com&oq=tgv+shaft+seal+site%3Alegacygt.com&aqs=chrome..69i57.7886j0j8&sourceid=chrome&ie=UTF-8 The link Max posted is for an '05, which from the sound of it is not what you have. This may help: http://legacygt.com/forums/showpost.php?p=4487789&postcount=359 Link to comment Share on other sites More sharing options...
Max Capacity Posted May 3, 2018 Share Posted May 3, 2018 The link should have all the 4th gen there 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
DoDo1975 Posted May 3, 2018 Author Share Posted May 3, 2018 I do have a 2005 LGT. However it is exactly as described. If you remove the cover plate there is a little shaft sticking out, and there is a shaft seal/gasket on this shaft. That is where the leak is coming from under 2-3 PSI of smoke; and it takes a little while to get there. Apparently a new TGV costs $800. Engine is out of the bay right now on the floor of the mechanics shop so likely time to do it is now. Trying to determine if there is a way to fix the seal (which just slides up and down the shaft) without replacing the entire TGV. Will check out the links. I am assuming this is the source of my intermittent cylinder 3 misfire code and the not so intermittent rough idle. In another thread someone mentioned the donut gasket issue, however I can't find a thread about this. Link to comment Share on other sites More sharing options...
relative4 Posted May 3, 2018 Share Posted May 3, 2018 The "donut gaskets" are the intake manifold gaskets. Replacing these both above and below the TGVs is a good idea while the engine is out. Link to comment Share on other sites More sharing options...
DoDo1975 Posted May 3, 2018 Author Share Posted May 3, 2018 Can you just seal up the whole TGV assembly cover. I assume the little hole in the bottom is where they draw the air from to make the swirl? If it was sealed up would this cause a code? Does just using some RTV on that shaft seal to keep it in place actually work for people? Link to comment Share on other sites More sharing options...
DoDo1975 Posted May 3, 2018 Author Share Posted May 3, 2018 Sorry to nag here but cant find the answer anywhere. The plate I am asking about is on the opposite end from the actuator. It covers the far end of the shaft that the TGVs are on and this is where my leak is coming from. Since the tgvs aren't serviceable, it seems logical to just seal up this plate to prevent any further boost leak problems if the shaft seal comes loose again. I need to let the mechanic know what to do ASAP. Either $1k to replace entire TGV or free to seal up that TGV cover plate. Does anyone see a problem with doing that or has anyone done this before? Link to comment Share on other sites More sharing options...
Max Capacity Posted May 3, 2018 Share Posted May 3, 2018 JB Weld may work, now that you've given me a exact location, I seem to recall this problem in the past. PM "m sprank" Mike will know the fix. He has a real repair shop and sells parts, remember to support him for his help. 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
VespaGTS Posted May 4, 2018 Share Posted May 4, 2018 Also, once you fix it smoke it again. Sometimes the bigger leaks hide the smaller leaks by letting the smoke out in volume at the bigger leak. I sealed the ends of my TGV and I still get lower than perfect 1.0 DAM numbers. Smoking it again in about an hour. Another mistake that happens with smoking for leaks is not letting the smoke run long enough. Do it for about 30 minutes. Link to comment Share on other sites More sharing options...
DoDo1975 Posted May 5, 2018 Author Share Posted May 5, 2018 Vespa, When you say sealed the end of your TGV, so you mean you sealed the sensor, or just the seal on the end of the rod? Link to comment Share on other sites More sharing options...
VespaGTS Posted May 8, 2018 Share Posted May 8, 2018 Sorry for the late reply. Just the end with the caps. On the drivers side front which is easy to get do. The passenger side is tucked behind a lot of hardware above the turbo. I did everything I could to unscrew the phillips heads holding that plate on but could not get it off. So I went caveman on it and used a flat head screw driver to break the phillips heads off and the plate fell away. It is a finishing plate only so no harm no foul. This gave me access to the leaking area and it is now completely sealed up. Link to comment Share on other sites More sharing options...
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