BMW 330i 2009 - Misfire, Rough Idle, P0430, Diagnostics Help

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Mon 21 Mar 2016 12:29
BMW 330i 2009 - Misfire, Rough Idle, P0430, Diagnostics Help - Jake181
Hi guys,

looking for some help with diagnosing an issue on my BMW 330i N53.

I have recently had a rough idle/misfire problem on my car, i replaced the spark plugs in an attempt to try and solve the issue, however i had to swap back to the old ones as i purchased the wrong plugs, i did notice that the bank 1 plugs were very sooty, also the misfires are occurring in cylinders 1 to 3, mainly cylinder 3.

Anyway i put the car back together and left it how it was, i then had the engine light come on with a P0430 code (Catalyst System Efficiency Below Threshold (Bank 2)) and so i then logged the O2 sensors, here are the graphs for bank 1 and 2 respectively:

s30.postimg.org/3lds154f5/Bank_1_Cat.png

s9.postimg.org/fug2ydwjj/Bank_2_Cat.png

It seems strange that I'm having issues with bank 1 but the fault code that could cause the issues I'm having is with bank 2.

Could it be just coincidence?

What do you guys think?
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Mon 21 Mar 2016 18:57
BMW 330i 2009 - Misfire, Rough Idle, P0430, Diagnostics Help - elekie&a/c doctor

The graphs of the sensors are no where near accurate enough to have any meaning.The fault code you have is the result of a problem ,not the cause.I think you are barking up the wrong tree.This engine runs an Hpi direct injection system and suffer with injector and fuel pump issues (in tank and engine driven).I think you need to get the fuel pressure system tested.

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Mon 21 Mar 2016 19:34
BMW 330i 2009 - Misfire, Rough Idle, P0430, Diagnostics Help - medview

Hi

The most likely cause of your problem is faulty fuel injectors. Chances are that you need to replace all 6 of them, if you plan to keep the car for some time.

If any injectors have been replaced it's worth checking that the ECU has the right calibration settings for the replacements. You can't just swap them out.

This engine is the first BMW generation with direct injection and both injectors and the fuel pumps give trouble. The fuel pressure is much higher than previous models. The injectors have been thru 10+ improvement iterations, they were that troublesome.

Joe

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Tue 22 Mar 2016 12:59
BMW 330i 2009 - Misfire, Rough Idle, P0430, Diagnostics Help - Jake181

thankyou,

I could not increase the accuracy of the graphs using the software i have which is pretty annoying.

Would the injectors be covered under a recall or warranty with BMW?

Thanks for the replies

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