boxpin Posted May 21, 2013 Report Share Posted May 21, 2013 I dont know what I am battling at this point. If I stomp to WOT and get past 20psi the boost just stops. The RPMs stay but there is no power because the boost is gone. If feels like when I was stock and hit fuel cutoff. If I let off the gas and get back into it boost comes on again strong. Its like there is a limiter or something. I can gradually bring it up ok but cant stab it. I was running an ARD TCV then went to a HKS EVC and still have the same issue. MBC test is next(edit:can see by the video its not the problem). On the intake side I have swapped out the HKS BOV which definately made a difference in holding boost but once I hit that 20psi...boom, gone. I dont know if its fuel being shut off, my AFRs are 11.9 on boost, when the boost falls it goes to 13.4 but that is expected in the situation I guess???. I cant think of anything else causing it other than the BOV is releasing but I purposely put that stupid whistle nozzle on it so I could hear if that was going on....not a peep. So if its not the wastegate releasing or the BOV releasing then it seems to me that it would be fuel shutting off (255 walbro and greens). So what would trigger that? Here is a video of the wastegate in action. Realized I slammed my glasses in the hood at 1:10, Boost fail at 1:55 and 2:30 http://www.youtube.com/watch?v=BwqhAiCUCl8 So, looks like the wastegate is not opening and the BOV is not opening. What could it be? Could the ECU back off timing? Here is in the cabin. Sorry the sun is out and hard to see the tach. The boost gauge is a 20psi gauge to give you an idea of where the needle should go. http://www.youtube.com/watch?v=wbKwnYmP7aA Link to comment Share on other sites More sharing options...
Zappo Posted May 21, 2013 Report Share Posted May 21, 2013 MBC won't help. I assume your max boost is 20 psi? The wastegate pops open at that and closes right away. Check all your hoses and clamps on the pressure side. Link to comment Share on other sites More sharing options...
fwdGTP Posted May 22, 2013 Report Share Posted May 22, 2013 That's pretty weird, I've never had something weird like that happen. I was thinking maybe it was gonna be spark blowout or something til I watched the video. I wish I could help you here, seems like wastegate issue most likely to me though. Link to comment Share on other sites More sharing options...
phonsa Posted May 22, 2013 Report Share Posted May 22, 2013 Could it be that your Green injectors are maxed out? Link to comment Share on other sites More sharing options...
fwdGTP Posted May 22, 2013 Report Share Posted May 22, 2013 Injector maxout will just lean, not drop the boost like that. It's not even leaning out much if any iirc, so I doubt it could be an issue. Really seems like a boost control issue, try running just wastegate actuator boost, line from turbo straight to it and see what the boost is, should hold constant 10/12 psi or whatever the actuator is set to. If it doesn't do that then maybe the actuator has an issue. Link to comment Share on other sites More sharing options...
fwdGTP Posted May 22, 2013 Report Share Posted May 22, 2013 But now watching the video again it looks like the wastegate doesn't even open... And if it does it is a very little amount, not enough to drop the boost to 0 I would think. I would say possible boost leak, but it wouldn't run the proper afrs like it is, would run unbelievably rich and probably misfire. I really seems like the turbo just isn't bringing anything in at all.... But still try a boost leak test, might be able to find the issue that way though. Link to comment Share on other sites More sharing options...
fattmatt805 Posted May 22, 2013 Report Share Posted May 22, 2013 sounds like a hose or coupler "sucking" shut pre turbo? Link to comment Share on other sites More sharing options...
boxpin Posted May 22, 2013 Author Report Share Posted May 22, 2013 sounds like a hose or coupler "sucking" shut pre turbo? Considered that so we took the filter out, opened the air box and tried. I can run 18psi and have it not do this. Link to comment Share on other sites More sharing options...
Simply Volvo Posted May 22, 2013 Report Share Posted May 22, 2013 Do you have anway to check ignition timing? Anyone you know have a scanner with live data you can barrow or an ELM327? Just to clear things does the boost completely go away or just power? Link to comment Share on other sites More sharing options...
boxpin Posted May 22, 2013 Author Report Share Posted May 22, 2013 Do you have anway to check ignition timing? Anyone you know have a scanner with live data you can barrow or an ELM327? Just to clear things does the boost completely go away or just power? If you open the cabin video and run it in HD full screen you can see the boost go to zero. I do have a scanner and an ELM327 (never got the ELM to connect though). Is feels to me like the timing is backing off. What 'free' software will work with the ELM? Its been awhile and maybe its time to try again. Link to comment Share on other sites More sharing options...
Simply Volvo Posted May 22, 2013 Report Share Posted May 22, 2013 Ah okay wasnt 100% sure. Dont see why ignition pull would *completely* kill the boost like that. According to a few maps the max the ecu can pull is 15 degrees. And everytime it hears a knock it reatards 2.25 degrees. Starting to think its more of a hardware issue rather than a ecc issue mainly because it works fine at 18 but at 20 everything goes down hill and boost drops to 0. Is it a bluetooth ELM? If you have a android and its bluetooth you can use torque. If its a usb ELM you can just use a serial terminal or wOBD. Link to comment Share on other sites More sharing options...
Zappo Posted May 22, 2013 Report Share Posted May 22, 2013 BOV issue? Link to comment Share on other sites More sharing options...
Platinum 850 Posted May 22, 2013 Report Share Posted May 22, 2013 If I had to guess I would assume its a severe boost leak on your couplers holding your intercooler piping together... Think of a tear that only opens up at a certain pressure... This is again only assuming your BOV is fully secure... I would tend to think its hardware and not your tune or boost control thats doing it... Even if a wastegate actuator went wide open, you would still have residual boost in your IC pipes downstream of your turbo. The only way your boost gauge goes from 20psig to 0psig in a blink of an eye is pressure loss in your IC piping... re-check your BOV and check all of your couplers... There is handfull of different ways to pressure test your piping setup without actually having the engine running... If you have a air compressor and 20minutes of spare time you can get all of your IC piping pressure tested... I normally would disconect the piping off of my throttle body, and I would simply pressure test the piping assembly including the intercooler. plug the turbo inlet, and the pressure port off of the turbo housing. If you are targeting 20psig then you can pressure up to 22-25psig and hold for 10minutes. you'll find out very quickly if you have leaks, and where they are. Link to comment Share on other sites More sharing options...
boxpin Posted May 22, 2013 Author Report Share Posted May 22, 2013 BOV issue? Thought that so I replaced it and put that whistle tip on it so I could hear it....it does not whistle until I let off the pedal. With the boost dropping like a rock it would whistle. Ah okay wasnt 100% sure. Dont see why ignition pull would *completely* kill the boost like that. According to a few maps the max the ecu can pull is 15 degrees. And everytime it hears a knock it reatards 2.25 degrees. Starting to think its more of a hardware issue rather than a ecc issue mainly because it works fine at 18 but at 20 everything goes down hill and boost drops to 0. Is it a bluetooth ELM? If you have a android and its bluetooth you can use torque. If its a usb ELM you can just use a serial terminal or wOBD. USB Elm. I still need to know of a free software to try. If I had to guess I would assume its a severe boost leak on your couplers holding your intercooler piping together... Think of a tear that only opens up at a certain pressure... This is again only assuming your BOV is fully secure... I would tend to think its hardware and not your tune or boost control thats doing it... Even if a wastegate actuator went wide open, you would still have residual boost in your IC pipes downstream of your turbo. The only way your boost gauge goes from 20psig to 0psig in a blink of an eye is pressure loss in your IC piping... re-check your BOV and check all of your couplers... There is handfull of different ways to pressure test your piping setup without actually having the engine running... If you have a air compressor and 20minutes of spare time you can get all of your IC piping pressure tested... I normally would disconect the piping off of my throttle body, and I would simply pressure test the piping assembly including the intercooler. plug the turbo inlet, and the pressure port off of the turbo housing. If you are targeting 20psig then you can pressure up to 22-25psig and hold for 10minutes. you'll find out very quickly if you have leaks, and where they are. If I have time today I will do this. I made some fittings about a year ago for pressure testing. My only concern is why would it drop to zero and not build again. I would think if there was a tare in a hose that it would build boost again after getting back down in the lower boost range. Link to comment Share on other sites More sharing options...
Zappo Posted May 22, 2013 Report Share Posted May 22, 2013 Because it drops to 0 and doesn't go into vacuum. Only when you go into vacuum and give it gas after that it gives you boost. This is why I said to check all your connections. It will only get worse if it is. I have seen a hose with a split in it that would hold 5 psi, but blow open above that. It eventually ripped open enough that it wouldn't hold boost at all and the person finally found it. Link to comment Share on other sites More sharing options...
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