Question about 2004 BMW 3 Series

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Bank 1 O2 sensor swaped with Bank 2 O2 sensor

I have an 04 325i and the engine went. I replaced it with a 2002 325i engine. I didn't replace computer. The check engine light is on and says that bank 1 sensor 1 is crossed with bank 2 sensor 1. The O2 sensors that came with new engine are for 2002 325i and the ones on the exhaust are the ones that are for the year model 2004. And computer was never flashed when the engine was swapped. Any one know what I should do?

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Hi Adam, I believe the most cost effective action for you is to get the management system designed for your engine. When doing so it may well be required that you also purchase the wiring harness that goes with the replacement unit. Regards John

Posted on Nov 28, 2013


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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: I have a 2000 323i. We have error code P1520.

i would not try the crank sensor just yet first off they **** to replace properly and you wont want to do that just yet, make sure it is the same code that has come back on as far as the banks are concerned on that enging the m52 the front 3 cly are bank 1 and the back 3 are bank 2, so unless it is talking about O2 sensors that is irrelivant, are you sure you replaced the correct sensor? it is the on in front on the engine with NO wire tail on it make sure it is plugged in correctly, this car is VERY good at knowing the difference between a cam sensor and a crank sensor the other guy does not know what he is talking about

Posted on Mar 31, 2009

  • 667 Answers

SOURCE: Help 10 codes on 323i!

These codes will have to be cleared and the car driven through a drive cycle, maybe a couple of times, is the check engine light off? Also you should check your MAF sensor it may need to be cleaned or replaced and makes sure there are no holes in your intake tubing. Hope this helps, let me know.

Posted on Dec 15, 2009

  • 279 Answers

SOURCE: what is the location ofttgen sensor, bank 2

Its located in the exhaust manifold on the passenger side,its the sensor closest to the rear of the engine.

Posted on Feb 07, 2010

  • 972 Answers

SOURCE: My 1995 525i has fault code 12210 O2 sensor

if the 02 sensor is unplugged and you are reading a scan tool from the diagnostic link then of course the 02 reading is wrong
if you are using a volt meter right at the connector thats on the sensor then the 02 will read lean because the heating elements in it are disconnected when you unplug it
check 02 voltage with engine warmed up and 02 sensor connected you will have to pierce insulation with your probe

Posted on Mar 22, 2010

  • 153 Answers

SOURCE: Hi there my problem is not quite the same,mine

I would start by having the fault code deleted, run the car again until the problem occurs, then plug in again and check for the current code, if same code appears, get the sensors checked ( they can be checked on the car )

Posted on Oct 05, 2010

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