jvanen Posted November 7, 2003 Share Posted November 7, 2003 Hey guys need some help. It sounds like an Air gun is full on under my hood when boosting. The engine won't Idle but runs fine while going down the road. when the turbo kicks in thats when the air gun sound goes off. Also the sound seems to be coming from right in front of me just on the other side of the fire wall. I seem to have a boost leakage somewhere under my hood and I can't find it for the life of me! Its not a hose. I've checked them all 100 times already. My EGR valve is good. My timing is all dead on. The engine is fresh with only 15k on it. The Injectors are all good, plenty of fuel, plenty of spark. My MAF is good to and woks properly. All Hoses are on tight and clamped down. When the engine first starts its like it can't hold its vacum for some reason. Could my vacum selinoid be causing this? It is a very very loud sound, so much that it takes time for the turbo to catch up in air pressure to compensate for the loss.... So I highly doubt that.. tell me whats up...maybe I'm smoking to much crack or what Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted November 7, 2003 Share Posted November 7, 2003 Do you have a BOV installed? It might be leaky. When I first installed mine, like an idiot I left the vacuum hose off of it.... when I hit boost it would just stay wide open and vent the whole time... at idle it didn't want to idle... this was also before I recirculated it... after I did that and hooked up the vacuum hose all was well. Besides the idle, is there anything else indicating that you have a problem? The idle issue could be lots of things. You might just be hearing the sounds the turbo is supposed to make... I know when I get on it in my car the whoosh of air from the turbo is so loud it sounds like a jet engine going off under my hood... for a while I thought that wasn't right but then I heard other people driving turbo'ed cars and hear them making that same sound... the things are loud man. I also spent a lot of time looking for leaks but found none (other than when the BOV was leaking). Also, if you really were leaking badly, you'd definately be able to tell... as soon as you hit boost you're car would start choking badly and would probably see smoke from the exhaust... as all that air escaping would cause the car to run super rich (the MAF doesn't know that all the air it's already measured is leaking out). This was another symptom when my BOV was leaking. As far as it needing to 'catch up' this could just be turbo lag.... Only other thing I can suggest is the usual trick for looking for vacuum leaks... if it leaks out under boost it should be a vacuum leak at idle. Get a can of carb cleaner and while the car is running spray everything, spray around the intake manifold, throttle body, turbo outlet... if you have a leak the idle should be effected when you spray. Quote Link to comment Share on other sites More sharing options...
jvanen Posted November 7, 2003 Author Share Posted November 7, 2003 Ok then, I"ll start with the carb choke cleaner and see what I can find. I'll also see what I can do about checking my BOV and making sure its not the cluprit. I'll keep you guys updated .....and Hey...Thanks Quote Link to comment Share on other sites More sharing options...
jvanen Posted November 7, 2003 Author Share Posted November 7, 2003 IT was the BOV. I found the leak with the carb choke cleaner. The engine totally changed rmp when I sprayed it down. When I disconnected the arm the BOV it was pointing to the Firewall. I'm thinking that it was engaged/letting the air run right past. IF I was able to bend the arm back to the angle it needed to be at...I"m thinking I'd be alright. "m also thinking that this give me an excellent excuse to get a nice new adjustable one. What do you think? Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted November 7, 2003 Share Posted November 7, 2003 That's why I recirculated my 1st gen. DSM BOV. If it happens to leak off boost, I don't care, as the air is still in my intake. I don't have any issues with boost pressure, so I know it's sealing at boost. What "arm" are you talking about? Quote Link to comment Share on other sites More sharing options...
jvanen Posted November 8, 2003 Author Share Posted November 8, 2003 The arm is about 6-8" long right above the actual turbo itself. I beleive its called the By-pass contoller in the book. I guess It opens the waste gate on the exhaust side... Its spring loaded but its all one way I don't know how it manages to shut the waste gate..... Quote Link to comment Share on other sites More sharing options...
fl327 Posted November 8, 2003 Share Posted November 8, 2003 thats the wastegate actuator, it could be broken somehow, causing the pov to vent. it should be secured to the turbo by two bolts on comp housing and a clip on the arm, make sure vacum lines to it are intact, sounds like youre overboosting and the pov is venting. Quote Link to comment Share on other sites More sharing options...
jvanen Posted November 9, 2003 Author Share Posted November 9, 2003 Hey I replaced those 3 little vacum lines just to make sure...Still no difference. When many of these problems started happening is after my Alternator went. It managed to blowout my headlights and the small fuse by the voltage regualtor. the car hasn't run right since. I replaced the headlights and put a new alt in and I thought things were all ok. But then this overboosting problem came up and she is running 10 mpg nbw. What about that little vacum selenoid deal by the AFM? I'm starting to Zero in on it. Doesn't it have something to do with the Idle of the car? perhaps I burnt up that little dude. I"m going to take it off when I get home and see what I can find. My goal is atleast get the thing to Idle properly and then perhaps take on this boost leakage. Oh yeah the car won't Idle less than 2g, and it purred like a kitten before my alt went. If any of you can figure this riddle out let me know! later, John jvanen@hotmail.com Quote Link to comment Share on other sites More sharing options...
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