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Model specific boards => Golf mk4 => Topic started by: jamie1989 on 09 October 2012, 22:04
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Stage 2 AGU k03s
Normaly boosting upto 22psi.
Today its not boosting over 12psi?
Plugged it in no fault codes at all.
Swapped mafs no different, unplugged N75 it then boosted upto 10psi so plugged it back in.
No pipes have blown off but when on boost you can hear a loud hissing noise?
Im almost certain its mechanical rather than sensors etc.
Surely if I had a boost leak it would still boost upto 22psi but drop dramatically?
Any suggestions? My next call would be to remove the bumper and remove every boost pipe and check for splits but still cant get my head around only boosting at 12psi and holding it there, sounds like limp mode.
PLEASE HELP lol
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Sell it :whistle:
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Its been on my mind as I want to upgrade but it was only the other day I said it never breaks down on me :laugh:
Technically it hasnt broken down but its annoying to say the least!
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Had a thought an changed the ignition amp an no difference.
No flat spots an strong pull to 12psi but nothing more :sad:
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12psi and a loud hissing sound means a big leak somewhere mate!
Log airflow from the MAF and see what you're getting, if it's 170g/s + then it's still pulling it in, and losing it somewhere between the MAF and the inlet.
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Will have to check later, I hope it is a boost leak tbh.
Just have to find it now :grin:
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Good look finding it dude :grin:
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Piping somewhere. does it not run s bit lumpy on idle?
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Nah not lumpy at all :cry:
It runs perfect infact and pulls hard upto 12psi then nothing.
Whilst I was driving through a lane last night I can hear a loud hissing noise though so sounds like air is escaping somewhere.
Im hoping its the exhuast bung in the map sensor hole :grin:
Everything else should be 100%.
I notice a BIG pop and blame on Sunday though so wondering if that had anything to do with it haha
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Maybe the wastegate not seatin properly so not spinning up the turbo properly if not sounds like a leak :undecided:
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I was thinking about the wastegate but I cant see it being that.
Any how when I get home I will remove and refit the actuator.
Remove all the boost pipes and replace and see if I can find any splits.
Shouldnt be a major problem as its still boosting upto 12psi.
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It can only be a leak given what you have said
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I hope so buddy.
Just finding the bugger now, canty be too hard as im losing 10psi straight away.
I just think its odd its peaking at 12psi and staying at 12psi lol
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I'd check all the pipes to the FMIC, I know some of mine feel like they loosen over time, I go around and nip them up every time I am under the car, also remember to look for oil on pipes as that'll help you find a boost leak.
Do you have the N249 and N112 either removed or bypassed using silicone tubing?
Check the DV connection and any Ts that go into a boost gauge
Check the one under the middle of the inlet manifold and ontop of the TB
Does your FMIC still use the pancake pipe? at the back of that the connection is a joke...
trying to remember all the ones I have blanked off lol
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I have AGU buddy soo
- No N112 or N249
- Checked DV and all good
- Iv never noticed the fmic clamps coming loose :huh:
- My THS fmic has a pancake delete but still uses jubilee clips :cool:
- My boost gauge is t'd in the FBR but all tubing is new silicone and all tight
Best thing to do is remove the wheel and bumper and strip all the boost pipes from the turbo to inlet and check everything.
Whats buggin me is when I left my boost gauge unplugged before as soon I hit boost the car felt like a fart but now there is a strong pull but only to 12psi :sad:
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Your THS uses the delete, so you mean you have custom piping, does that then attach to the standard charge pipe or is that custom too?
Just look for oil and you will find your issue :wink:
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Yeah basically buddy, the THS pancake delete is just a intercooler pipe which replaces the pancake pipe.
This then attaches to the charge pipe, but the charge pipe on AGU's use jubilee clips.
I have a feeling its something to do with the actuator but il check the pressure on it later an go from there.
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Heres my list for tonight :grin:
- Check actuator pressure/bracket
- Check DV and pipework
- Check inlet manifold and each takeoff
- Check charge pipe, pancake delete, boost pipes including map sensor blank.
- Check FMIC core.
Iv already replaced/changed the MAF and ignition amp and plugged it in with no fault codes.
Iv unplugged the N75 which made it run at 10psi so its not that.
Will update later unless someone knows to check anything else?
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is it not dangerous to unplug the N75 :undecided:
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I wouldnt think so id like to imagine it would throw it in limp.
Cant harm to check if it was dead or not lol
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it's not odd that it's reaching 12psi and staying there at all, your system is obviously no longer airtight above 12psi, the hissing you're hearing is the turbo trying to make more boost, and it's all leaking out at a steady rate from somewhere! it's pretty logical that a leak would give you stable, but reduced boost.
Unplugging the N75 electrically isn't dangerous at all, the N75 valve default position when not powered is 100% open, so it allows free flow from the charge pipe to the actuator, so by running the car with the N75 unplugged, you're just running actuator pressure, and reduced power.
I've actually got a switch wired into my N75 wires so I can switch between actuator pressure for normal use or full boost for fun.
On a ko3s setup unplugging the N75 will take you back to around 150-160bhp. On my hybrid setup actuator pressure is 274bhp, and full boost is around 300, so it's a measurable difference.
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Prawny I love you haha
:grin:
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Awesome news :) I'm in :cool:
Does that mean you want to buy my ko4 hybrid setup in a few months when I go GT28? :rolleyes:
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Possibly :cool:
I cant wait to get home and strip the little sh!t now.
Im hoping the THS intercooler iv bought off Chris has a leaky map sensor as hes plugged it with an exhuast bung and silicone but it seemed fine when I put it on.
I will check everything and report back here.
PM me how much your looking for and when your looking at selling up :whistle:
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Mine leaked... which is why I had it welded over
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Split pipe from charge pipe to pancake pipe lol nice big one too :grin:
(http://i892.photobucket.com/albums/ac125/jamierees1989/2012-10-10191940.jpg)
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Anyone got one? lol
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Chris might...
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Dont think chris does as hes just sold his. Ill have a scout about though.
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Mines just started doing this! But I'm at 15 psi but I've got a hissing and a weird chattering, fluttering sound. How did you find your boost leak mate? With a pressure tester or something?
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Chris if you can let know that would be great.
Haha Dan I checked from turbo to inlet and lucky enuf was my 3rd pipe lol
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glad you found what the problem is dude :cool:
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Got one here pal. £15 onto your doorstep
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PM'd
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Cheers Andrew hopefully it will be all fixed for Sunday too :cool:
Still need to paint the wheels :grin:
Thanks again Chris for sorting this out.