Help! 2F9E and 30FF under load

Boostin402 · 07-19-2019, 08:02 PM

Hey guys I've been having this issue with my 07 335xi under heavier load(75+ throttle) I get a check engine light and these two codes:
2F9E: thermic oil level sensor
30FF: BOOST UNDER TARGET
I have replaced the oil level sensor and still have this issue any advice would help!
Mods:
Jb4 g4
Straight pipe from catback
Vrsf chargepipe with his
All new vacuum lines

Boostin402 · 07-20-2019, 02:18 AM

I get small hiccups shifting as well recently changed my ofh gasket and intake gaskets but have had this problem before that could the 2f9e cause the 30ff under boost target? I installed a new oil level sensor which shoulve taken care of the thermic oil sensor problem but still happens on heavy acceleration.

Silent9n54 · 07-20-2019, 02:32 AM

try replacing boost solenoids

Boostin402 · 07-20-2019, 02:05 PM

Quote:

Originally Posted by Silent11N54

try replacing boost solenoids

Boost solenoids are different from vanos solenoids correct? I've replaced camshaft, crankshaft and vanos solenoids as well as the vanos filter bolts so I guess I'll try those next thanks for the input!

Bimmer_Engineer · 07-20-2019, 02:39 PM

Quote:

Originally Posted by Boostin402

Boost solenoids are different from vanos solenoids correct? I've replaced camshaft, crankshaft and vanos solenoids as well as the vanos filter bolts so I guess I'll try those next thanks for the input!

Boost solenoids are a possible culprit, but boost leaks are very common too. There's a DIY on here on how to check for boost leaks.

dpaul · 07-20-2019, 04:40 PM

Before starting to randomly replace components, you might want to record a log. There are about 59 million reasons why you might get an underboost code

If you don't know how to log, there are plenty of threads about it.

BTW, it is extremely unlikely that a problem with the oil sensor will cause a boost problem. I actually cannot think of a scenario in which it would.

Boostin402 · 07-22-2019, 05:23 PM

Quote:

Originally Posted by dpaul

Before starting to randomly replace components, you might want to record a log. There are about 59 million reasons why you might get an underboost code

If you don't know how to log, there are plenty of threads about it.

BTW, it is extremely unlikely that a problem with the oil sensor will cause a boost problem. I actually cannot think of a scenario in which it would.

I will log I have jb4 with the USB cable thanks for the input. That's what I thought too but I get the codes at the same time when I go into higher rpms

07-19-2019, 08:02 PM	#1
Boostin402 Enlisted Member 0 Rep 39 Posts Drives: 07 335xi sedan Join Date: Jul 2018 Location: Lincoln ne iTrader: (0)	Help! 2F9E and 30FF under load Hey guys I've been having this issue with my 07 335xi under heavier load(75+ throttle) I get a check engine light and these two codes: 2F9E: thermic oil level sensor 30FF: BOOST UNDER TARGET I have replaced the oil level sensor and still have this issue any advice would help! Mods: Jb4 g4 Straight pipe from catback Vrsf chargepipe with his All new vacuum lines
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07-20-2019, 02:18 AM	#2
Boostin402 Enlisted Member 0 Rep 39 Posts Drives: 07 335xi sedan Join Date: Jul 2018 Location: Lincoln ne iTrader: (0)	I get small hiccups shifting as well recently changed my ofh gasket and intake gaskets but have had this problem before that could the 2f9e cause the 30ff under boost target? I installed a new oil level sensor which shoulve taken care of the thermic oil sensor problem but still happens on heavy acceleration.
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07-20-2019, 02:32 AM	#3
Silent9n54 Captain 580 Rep 940 Posts Drives: 2007 E92 335i Join Date: Jul 2017 Location: Vancouver, Canada iTrader: (0)	try replacing boost solenoids
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07-20-2019, 04:40 PM	#6
dpaul Lieutenant Colonel 655 Rep 1,893 Posts Drives: 2009 E90 335xi, 2011 E93 M3 Join Date: Dec 2012 Location: Boston iTrader: (3)	Before starting to randomly replace components, you might want to record a log. There are about 59 million reasons why you might get an underboost code If you don't know how to log, there are plenty of threads about it. BTW, it is extremely unlikely that a problem with the oil sensor will cause a boost problem. I actually cannot think of a scenario in which it would.
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