Boost leak?

jrsniper12453 · 05-05-2012, 01:43 AM

So my jb4 + meth was working fine up until one wot when it went limp ces and threw an underboost code. I cleared it and thought it was fine but now something is definitely not right. At high boost i can hear a whooshing (like air leaking) sound from the charge pipe area, and boost isn't getting up to levels it should be. But I checked and it's not throwing any codes. Why would there not be codes if it indeed is leaking?

jpsimon · 05-05-2012, 02:06 AM

I recently had a boost leak which was hard to find (and threw no codes) - it ended up being on the underside of the charge pipe where it meets up to the intake manifold. feel around underneath and see if that's where it is. Obviously a long shot but might as well give it a try

rader1 · 05-05-2012, 03:13 AM

Does JB4 auto code clear(I can't remember what it's called right now lol) hide boost leak codes?
Start with the basics; check all charge pipe, DV and FMIC connections.

robc1976 · 05-05-2012, 03:41 AM

Quote:

Originally Posted by jrsniper12453

So my jb4 + meth was working fine up until one wot when it went limp ces and threw an underboost code. I cleared it and thought it was fine but now something is definitely not right. At high boost i can hear a whooshing (like air leaking) sound from the charge pipe area, and boost isn't getting up to levels it should be. But I checked and it's not throwing any codes. Why would there not be codes if it indeed is leaking?

Check the lines behind the oil filter housing...mine where toasted and thru a 30ff code.

05-05-2012, 01:43 AM	#1
jrsniper12453 Second Lieutenant 14 Rep 229 Posts Drives: 335i Join Date: Mar 2008 Location: Las Vegas/LA iTrader: (0)	Boost leak? So my jb4 + meth was working fine up until one wot when it went limp ces and threw an underboost code. I cleared it and thought it was fine but now something is definitely not right. At high boost i can hear a whooshing (like air leaking) sound from the charge pipe area, and boost isn't getting up to levels it should be. But I checked and it's not throwing any codes. Why would there not be codes if it indeed is leaking? __________________ 2007 335i, Space Gray, Black/Alum, Sports, Prem, CA, Navi, iPod
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05-05-2012, 02:06 AM	#2
jpsimon Team Zissou 3163 Rep 10,200 Posts Drives: 2022 AWD M3 Comp - SMB Join Date: Dec 2006 Location: CT iTrader: (7)	I recently had a boost leak which was hard to find (and threw no codes) - it ended up being on the underside of the charge pipe where it meets up to the intake manifold. feel around underneath and see if that's where it is. Obviously a long shot but might as well give it a try Last edited by jpsimon; 05-05-2012 at 02:24 AM..
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05-05-2012, 03:13 AM	#3
rader1 Banned 71 Rep 2,197 Posts Drives: Cobb Stage 2+ 135i Join Date: Apr 2011 Location: Roanoke, VA iTrader: (0)	Does JB4 auto code clear(I can't remember what it's called right now lol) hide boost leak codes? Start with the basics; check all charge pipe, DV and FMIC connections.
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