strange 30ff. light throttle

fredcase · 06-11-2015, 10:07 AM

I am getting an occasional 30ff low boost only under light throttle conditions. If I'm cruising at a speed for a while and giver her a little gas I get the 30ff. Hits target 16psi no problem at full throttle. (map 2)

It was happening before with dinan stage 2, and seems a little more frequent being jb4, fbo now.

I changed both boost solonoids, vacuum lines and chargepipe still happening.

335NJ · 06-11-2015, 10:46 AM

Could be vacuum related, test the vacuum system to make sure there's no hidden leaks. I see you already did the common vacuum related things, but did you replace each line?

Other than that, maybe a faulty sensor?

Jeff@TopGearSolutions · 06-11-2015, 10:56 AM

Stock DV? Checked intercooler connections?

fredcase · 06-11-2015, 11:04 AM

Intercooler is ok. But am on stock dv's

mike@x-ph.com · 06-11-2015, 12:00 PM

Quote:

Originally Posted by fredcase

I am getting an occasional 30ff low boost only under light throttle conditions. If I'm cruising at a speed for a while and giver her a little gas I get the 30ff. Hits target 16psi no problem at full throttle. (map 2)

It was happening before with dinan stage 2, and seems a little more frequent being jb4, fbo now.

I changed both boost solonoids, vacuum lines and chargepipe still happening.

I was having that problem for a while.
Contacted Terry and he told me to upgrade to the newest firware. Got it fixed.
Make sure you have the newest firmware

fredcase · 06-11-2015, 12:28 PM

Quote:

Originally Posted by mike@x-ph.com

I was having that problem for a while.
Contacted Terry and he told me to upgrade to the newest firware. Got it fixed.
Make sure you have the newest firmware

Do have. Like i said. Itwas doing this before the jb4. So i dont hink its a software issue. If i had a leak, i wouldn't be able to hit boost wot.

I think something is sticking, either wastegate or dv. It happens immediatly after giving some gas radomly.

335NJ · 06-11-2015, 12:59 PM

Even though this issue was prior to the JB4, make sure all DUTY BIAS values are set to 0 in the interface. Assuming you're using firmware 28_7 & up.

fredcase · 06-11-2015, 01:17 PM

Quote:

Originally Posted by 335NJ

Even though this issue was prior to the JB4, make sure all DUTY BIAS values are set to 0 in the interface. Assuming you're using firmware 28_7 & up.

Done. Just reset adaptations this morning also. See if that helps.

06-11-2015, 10:07 AM	#1
fredcase Captain 261 Rep 776 Posts Drives: Bmw=trash Join Date: Mar 2014 Location: Noyb iTrader: (1)	strange 30ff. light throttle I am getting an occasional 30ff low boost only under light throttle conditions. If I'm cruising at a speed for a while and giver her a little gas I get the 30ff. Hits target 16psi no problem at full throttle. (map 2) It was happening before with dinan stage 2, and seems a little more frequent being jb4, fbo now. I changed both boost solonoids, vacuum lines and chargepipe still happening.
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06-11-2015, 10:46 AM	#2
335NJ Colonel 533 Rep 2,872 Posts Drives: 2008 335i 6MT E90 Join Date: Feb 2014 Location: NJ/Philadelphia Suburbs iTrader: (1)	Could be vacuum related, test the vacuum system to make sure there's no hidden leaks. I see you already did the common vacuum related things, but did you replace each line? Other than that, maybe a faulty sensor?
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06-11-2015, 10:56 AM	#3
Jeff@TopGearSolutions 3441 Rep 79,211 Posts Drives: C6 Z06, 09 335i, 10 335xi Join Date: Dec 2008 Location: www.TopGearSolutions.com iTrader: (37)	Stock DV? Checked intercooler connections?
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06-11-2015, 11:04 AM	#4
fredcase Captain 261 Rep 776 Posts Drives: Bmw=trash Join Date: Mar 2014 Location: Noyb iTrader: (1)	Intercooler is ok. But am on stock dv's
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06-11-2015, 12:59 PM	#7
335NJ Colonel 533 Rep 2,872 Posts Drives: 2008 335i 6MT E90 Join Date: Feb 2014 Location: NJ/Philadelphia Suburbs iTrader: (1)	Even though this issue was prior to the JB4, make sure all DUTY BIAS values are set to 0 in the interface. Assuming you're using firmware 28_7 & up.
	Appreciate 0 Quote