Light acceleration hesitations, cannot run JB4, shaky idle

Evochuck · 02-11-2015, 07:48 PM

-For the past 3 days, I cannot floor my car, the second I go past 10 psi a check engine light lights up and is auto cleared, and JB4 switches automatically to map4 (stock)

-When Im stuck in traffic for a while my idle gets really shaky, issue seems to only happen when in a Jb4 map (not 0)

-When accelerating very lightly the car shakes and bogs (pretty hard to describe) then if I accelerate more its fine.

-Today the code 2C3B Lambda probe in front of catalytic converter, not plugged, showed up in map 0

-Please bear I did not have time to check anything as I get home and its very dark and its about -20 deg C over here.

-I ordered plugs as its been a while I changed them 35k kms(oem boschs), cant hurt to change em.

mod list is:
2009 335xi
-Jb4 usually in map5
-BMS backend pump flash
-catless downpipes
-runs on 91 octane all the time

Any ideas?

hemi to e90 · 02-11-2015, 08:14 PM

autoclear?

Evochuck · 02-11-2015, 08:22 PM

Quote:

Originally Posted by hemi to e90

autoclear?

JB4 feature, clears usualy unimportant codes, esp for catless downpipes

n54gte · 02-11-2015, 08:24 PM

usually symptoms like that are misfires. change the plugs or ignition coils

Evochuck · 02-12-2015, 06:15 AM

Anyone has a different opinion? Something related to the JB4 I might have missed?

02-11-2015, 07:48 PM	#1
Evochuck Lieutenant 69 Rep 404 Posts Drives: 335xi 09 Join Date: Jan 2013 Location: Montreal iTrader: (2)	Light acceleration hesitations, cannot run JB4, shaky idle -For the past 3 days, I cannot floor my car, the second I go past 10 psi a check engine light lights up and is auto cleared, and JB4 switches automatically to map4 (stock) -When Im stuck in traffic for a while my idle gets really shaky, issue seems to only happen when in a Jb4 map (not 0) -When accelerating very lightly the car shakes and bogs (pretty hard to describe) then if I accelerate more its fine. -Today the code 2C3B Lambda probe in front of catalytic converter, not plugged, showed up in map 0 -Please bear I did not have time to check anything as I get home and its very dark and its about -20 deg C over here. -I ordered plugs as its been a while I changed them 35k kms(oem boschs), cant hurt to change em. mod list is: 2009 335xi -Jb4 usually in map5 -BMS backend pump flash -catless downpipes -runs on 91 octane all the time Any ideas?
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02-11-2015, 08:14 PM	#2
hemi to e90 dat boost doe 238 Rep 1,823 Posts Drives: 10 335i 21 740li Join Date: Aug 2005 Location: nyc iTrader: (1)	autoclear? __________________
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02-12-2015, 06:15 AM	#5
Evochuck Lieutenant 69 Rep 404 Posts Drives: 335xi 09 Join Date: Jan 2013 Location: Montreal iTrader: (2)	Anyone has a different opinion? Something related to the JB4 I might have missed?
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