avatar382 Posted December 31, 2005 Share Posted December 31, 2005 So driving home today I noticed the car felt sluggish in 5th. I hit the gas WOT and look at the boost gauge... and, WTF? 2 psi? It slooooowly climbs to 5-6 psi and stays around there. In second, same story, execpt that by around 5000 rpm I get maybe 7 psi. I have a manual boost controller set to 12 psi, and normal behavior is that in the higher gears, it shoots right on up there once you get on the gas. So, what should I look for? probably an exhaust leak before the turbo, right? I swear my car sounds louder now, but it could very well be just my imagination. If it's not a leak, time to go turbo shopping eh? I have a VF11. I'm hoping that a TD04 from a WRX will just bolt right on where the old one was... This is very strange because the drop off in boost seems very sudden. Less than a week ago, everything was perfectly normal. I always thought that when turbochargers go, they go slowly... Quote Link to comment Share on other sites More sharing options...
Subarutex Posted December 31, 2005 Share Posted December 31, 2005 Whoa there turbo, there is more than one cause... A. Exhaust leak before turbo (at the heads, or at the turbo) B. Vaccuum leak (or rather, boost leak... check intercooler piping) C. Plugged exhaust down stream limiting flow Quote Link to comment Share on other sites More sharing options...
Skip Posted December 31, 2005 Share Posted December 31, 2005 my check mark goes beside Tex's "C" could be CCC Classic Cat Collapse Quote Link to comment Share on other sites More sharing options...
avatar382 Posted December 31, 2005 Author Share Posted December 31, 2005 I don't have any cats. Completely open exhaust. I'm taking apart all of my plumbing. Got to be a leak there, somewhere. Quote Link to comment Share on other sites More sharing options...
Dr. RX Posted December 31, 2005 Share Posted December 31, 2005 Make sure that you also remove any shielding that might be on the exhaust. I once looked at a car whos exhaust looked perfect, but had no boost. Once the shielding was removed we could see the rather large holes in the exhaust. Quote Link to comment Share on other sites More sharing options...
Skip Posted December 31, 2005 Share Posted December 31, 2005 Wait a second, this is the XT that I owned for a while there was a constant problem with the wastegate actuator mechanism I would examine this area for a stuck open wastegate this might explain the problem Quote Link to comment Share on other sites More sharing options...
avatar382 Posted December 31, 2005 Author Share Posted December 31, 2005 Update - So, I took the intercooler and all the intake piping completely apart. No holes/leaks anywhere in the intake, as far as I could tell. Turbo compressor shaft spun freely, and I couldn't detect any play at all. So, that's a relief. The only maybe strange thing I noted with the turbo is that it took a fair bit of force to move the wastegate. Is that normal? I could still move it by hand, but it seemed like there was a decently powerful spring holding it in place. Near 6000 RPM, it builds close to full boost, around 10 psi. Now, I definately think something is up with the exhaust. At high RPM, it sounds almost like something is rattling. Looking at the header visually, though, I can't for the life of me tell where it might be leaking. Also, and I don't know if this has anything to do with it, the engine seems to be idling a little higher than normal. Usually it idles around 1400-1500 rpm, and I noticed that it was idling at 1600-1700 RPM. It also sounds a bit different at idle. Hard to describe. Will a muffler/exhaust shop be able to determine the source of the leak? Or, what techniques can I use to try to find an exhaust leak? Quote Link to comment Share on other sites More sharing options...
avatar382 Posted December 31, 2005 Author Share Posted December 31, 2005 Skip- by stuck open, what way would the wastegate lever point? It looks like this: That's the closed position, right? Quote Link to comment Share on other sites More sharing options...
[HTi]Johnson Posted December 31, 2005 Share Posted December 31, 2005 If it isn't your waste gate, I'd say it's the up pipe. Right where it mounts to the turbo plate. I had the same problem, car was loud and barely any boost. This happened because my downpipe wasn't secured to the mounting point...on the tranny. In the pic, I can see that your downpipe isn't mounted to the tranny. I'd say you tore the uppipe right before the weld. Keep us updated. Quote Link to comment Share on other sites More sharing options...
WJM Posted December 31, 2005 Share Posted December 31, 2005 My vote is for a cracked header. Quote Link to comment Share on other sites More sharing options...
Skip Posted December 31, 2005 Share Posted December 31, 2005 It's been a while since I saw your setup so I went out to the turbo department and fished out a VF11 It looks like the arm should move a bit more for total closure of the wastegate. You may want to pull the head pipe back and look Quote Link to comment Share on other sites More sharing options...
BoostedBalls Posted December 31, 2005 Share Posted December 31, 2005 OK- check this out man: Check header for cracks / rust holes and cracks near the weld points. If all looks good: Take the clip off the wastegate lever and wire the lever tightly to the front of the turbo so the poppet will stay closed for testing. A strong spring would work also. This will at least tell you if it is the problem or not. If it still won't make boost, I would take your down pipe off and check for a large crack going from wastegate hole to exducer hole. A lot of them are cracked and till work fine, problem is, the cracks get burned open to the point where you get the symptoms you are having. Quote Link to comment Share on other sites More sharing options...
subiemech85 Posted January 1, 2006 Share Posted January 1, 2006 there may be foreign material blocking the flow of exhaust gasses in the turbo housing Quote Link to comment Share on other sites More sharing options...
avatar382 Posted January 2, 2006 Author Share Posted January 2, 2006 Update: Thanks for all the help! Turns out, the problem was ridiculously simple. One of the nuts securing the header to the head fell out, and the gasket at the head was broken. Huge exhaust leak. It's fixed now, and it is much, MUCH quieter. SICK amounts of power, too. Feels like a different car. Of course, it feels like that since I've been driving it with the 900 of my cc's venting exhaust to the atmosphere for who knows how long. I'm just so pissed at myself I didn't see the missing nut...amazing how it's the little details that get you! Quote Link to comment Share on other sites More sharing options...
[HTi]Johnson Posted January 2, 2006 Share Posted January 2, 2006 I still suggest mounting that downpipe to the tranny...you can see the point is mounts to. It's right to the left of the CV...the DOJ. Quote Link to comment Share on other sites More sharing options...
avatar382 Posted January 3, 2006 Author Share Posted January 3, 2006 I still suggest mounting that downpipe to the tranny...you can see the point is mounts to. It's right to the left of the CV...the DOJ. I definately will, thanks for the tip! I guess it's the vibrations that twist everything, huh? Quote Link to comment Share on other sites More sharing options...
Skip Posted January 3, 2006 Share Posted January 3, 2006 might want to add a simple heat shield for the DOJ boot also simple "U" of 1/2" steel - rad hosed onto the pipe with a 4" x 6" piece of sheet metal fastened to the other leg of the "U" A bell mouth or better - divorced pipe for the waste gate down pipe would also help Quote Link to comment Share on other sites More sharing options...
Subarutex Posted January 3, 2006 Share Posted January 3, 2006 Good to see it a was an easy fix. I was banking on it being A. Quote Link to comment Share on other sites More sharing options...
avatar382 Posted January 18, 2006 Author Share Posted January 18, 2006 Well, 300 miles later, I lost a nut on the driver's side now! (before it was passenger side) So, I got the real deal fasteners to get that header on there. Question, though - the stock fastener is like a stud, yet putting another nut on there, after putting some torque on it, the stud just fell out like if the threads were too small. I tried to put it back on and... the threads ARE too small! What gives? Quote Link to comment Share on other sites More sharing options...
subiemech85 Posted January 18, 2006 Share Posted January 18, 2006 on which issue is the problem? studs can pull threads out of heads Quote Link to comment Share on other sites More sharing options...
avatar382 Posted January 18, 2006 Author Share Posted January 18, 2006 on which issue is the problem?studs can pull threads out of heads Yeah, I think I stripped the threads from the head. How do I prevent doing this in the future? For now, I am just gonna put in on there in the other orientation with the correct hardware. (I have the TWE header with the four mounting holes) Quote Link to comment Share on other sites More sharing options...
idosubaru Posted January 18, 2006 Share Posted January 18, 2006 exhaust stud threads strip all the time. heli-coil time. stock headers have to be removed to do this, after that it's really easy to helicoil as there's no access issues. removing the header is annoying. Quote Link to comment Share on other sites More sharing options...
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