Jb4 small boost leak

DZ153 · 01-09-2015, 11:02 AM

Installed JB4 and for some reason I'm not hitting the usual 15-17 psi. I'm hitting max 10 psi so there's gotta be a leak somewhere. Tried both map 1 and 5 (only mods are jb4 and PE). I'm not an expert on the n55 so does anyone have suggestions on where to start looking for this boost leak? Thanks in advance

JETmn · 01-09-2015, 11:05 AM

Are you sure the JB4 is hooked up correctly? That sounds like stock boost levels. Are the steering wheel controls working?

mike5809 · 01-09-2015, 12:44 PM

Check charge pipe and intercooler couplers.

weehe126 · 01-09-2015, 01:28 PM

What gas are you using? If all you have is the tune, as the exhaust does nothing, you should only run map 1 which is 12psi. Stock is 8psi. Unless you have E40 there is no way you will hit 16+psi. Also, map 5 takes 3 third gear pulls to auto tune. It will only do 10psi untill you do the pulls.

wiskerbisskit · 01-10-2015, 08:06 AM

^what he said? If something wasn't tighten down you'd probably only be spiking to 3-4 psi then it would fall on its face.

AJF80 · 01-10-2015, 08:19 AM

You also need to make sure that your oil temp is warmed up. I dont remember the exact temperature but I recall reading somewhere that the JB4 will have stock psi until your car is warmed up.

weehe126 · 01-10-2015, 10:17 AM

Quote:

Originally Posted by AJN55

You also need to make sure that your oil temp is warmed up. I dont remember the exact temperature but I recall reading somewhere that the JB4 will have stock psi until your car is warmed up.

If under 160 it will only boost 8psi.

01-09-2015, 11:02 AM	#1
DZ153 Private First Class 32 Rep 103 Posts Drives: 2012 E92 335i xDrive Join Date: Aug 2009 Location: NJ - NY - PA iTrader: (0)	Jb4 small boost leak Installed JB4 and for some reason I'm not hitting the usual 15-17 psi. I'm hitting max 10 psi so there's gotta be a leak somewhere. Tried both map 1 and 5 (only mods are jb4 and PE). I'm not an expert on the n55 so does anyone have suggestions on where to start looking for this boost leak? Thanks in advance __________________ BSM/Coral Red '12 E92 335i xDrive
	Appreciate 0 Tweet Quote

01-09-2015, 11:05 AM	#2
JETmn Lieutenant Colonel 245 Rep 1,595 Posts Drives: 2011 335i xDrive Msport Join Date: Apr 2013 Location: Orlando iTrader: (0) Garage List 2011 335Xi [0.00]	Are you sure the JB4 is hooked up correctly? That sounds like stock boost levels. Are the steering wheel controls working?
	Appreciate 0 Quote

01-09-2015, 12:44 PM	#3
mike5809 Major 131 Rep 1,086 Posts Drives: '11 335i M-Sport [LeMans Blue] Join Date: May 2011 Location: York, PA iTrader: (7) Garage List 2011 BMW 335i M-Spo ... [9.66]	Check charge pipe and intercooler couplers. __________________ '11 335i M-Sport xDrive Coupe [LMB] COBB V3 & PTF Tune \| E45 \|4in BERK DP \| VRSF 5in FMIC \| BMS Intake \| ER CP \| Exotics Tuning CF Lip \| CF Diffuser \| Eibach Springs \| Bilstein Shocks '07 BMW 335i Coupe & BMW Z4 3.0i - Gone
	Appreciate 0 Quote

01-09-2015, 01:28 PM	#4
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	What gas are you using? If all you have is the tune, as the exhaust does nothing, you should only run map 1 which is 12psi. Stock is 8psi. Unless you have E40 there is no way you will hit 16+psi. Also, map 5 takes 3 third gear pulls to auto tune. It will only do 10psi untill you do the pulls.
	Appreciate 0 Quote

01-10-2015, 08:06 AM	#5
wiskerbisskit Private 2 Rep 92 Posts Drives: 2010 335i M-sport. Join Date: Jul 2014 Location: Ga iTrader: (0)	^what he said? If something wasn't tighten down you'd probably only be spiking to 3-4 psi then it would fall on its face.
	Appreciate 0 Quote

01-10-2015, 08:19 AM	#6
AJF80 Private First Class 109 Rep 178 Posts Drives: F90 M5 Join Date: Mar 2014 Location: Tampa, Fl iTrader: (1)	You also need to make sure that your oil temp is warmed up. I dont remember the exact temperature but I recall reading somewhere that the JB4 will have stock psi until your car is warmed up. __________________ \|F90 M5 \| F80 M3\| Lambo \| Last edited by AJF80; 01-10-2015 at 10:01 AM..
	Appreciate 0 Quote