BMW N51 bouncing rpms

jmporter_3 · 04-26-2024, 07:18 AM

I'm trying to figure out why my RPMs keep jolting the car at idle. At first I thought it was my EGR valve (I have an N51), but after cleaning it the cars RPMs still would still bounce up and down. At this moment I am cleaning my vanos solenoids to see if this will fix the problem. Is there anything else I'm missing? Could be the PVC?

Engine codes so here they are: P0420, P0430, P0140a

kacpere90 · 04-26-2024, 12:17 PM

Have you checked those codes already?

P0420 and P0430 are for low catalytic converters efficiency.

P0140A (as described here https://www.e90post.com/forums/showthread.php?t=593036) means - Secondary air injection system, bank 1 & 2 - insufficient flow detected. Problems with mixture can cause catalytic converters errors and unsteady RPMs

04-26-2024, 07:18 AM	#1
jmporter_3 Registered 0 Rep 1 Posts Drives: BMW E92 328XI Coupe (N51) Join Date: Apr 2024 Location: Garnet Valley, PA iTrader: (0)	BMW N51 bouncing rpms I'm trying to figure out why my RPMs keep jolting the car at idle. At first I thought it was my EGR valve (I have an N51), but after cleaning it the cars RPMs still would still bounce up and down. At this moment I am cleaning my vanos solenoids to see if this will fix the problem. Is there anything else I'm missing? Could be the PVC? Engine codes so here they are: P0420, P0430, P0140a
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04-26-2024, 12:17 PM	#2
kacpere90 Registered 0 Rep 3 Posts Drives: BMW E90 325i 2005 Join Date: Apr 2024 Location: Poland iTrader: (0)	Have you checked those codes already? P0420 and P0430 are for low catalytic converters efficiency. P0140A (as described here https://www.e90post.com/forums/showthread.php?t=593036) means - Secondary air injection system, bank 1 & 2 - insufficient flow detected. Problems with mixture can cause catalytic converters errors and unsteady RPMs Last edited by kacpere90; 04-26-2024 at 12:22 PM..
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