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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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

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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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Where is the O2sensor bank 1 at with a code of P0420. AND do I need to replace both sensors upstream and down. Or just the one that is showing up on the obd scanner.

Bank one is front side of cat. It should also tell u if it's cat 1 or cat 2. Depending on make an modle an yr. Catalyst 1 bank 2 is left cat back sensor. Catalyst 2 bank 2 is right cat back sensor. U do not have to replace upstream also. My o2 sensor Catalyst 2 bank 2 went bad. Had engine code for burning rich bank 2. Replaced tha down stream sensor an fixed problem runs better an better gas. This was in 97 gmc suburban. Idk what vehicle ur askin about. An I'm not to familiar with much about cars jus trucks an suvs.

Jan 02, 2017 | Cars & Trucks

1 Answer

2002 Santa Fe with P0031 code (O2 sensor, bank 1 sensor 1). Replace sensor, cleared code and code reappears. On the OBDII, the code shows under transmission and engine. Do I need to clear the code

I guess I should start by saying that trouble codes do not instruct the mechanic to replace a component. Only to check it.
Code 31 is for a problem with the heater circuit for that O2 sensor. The sensor is not warming up fast enough to satisfy the engine computer. Since you have replaced the sensor, the actual problem could be in the wiring or the source of power for the heater built into the sensor.

Sep 15, 2014 | 2002 Hyundai Santa Fe

3 Answers

2002 dodge caravan engine light on code showing p0135 .please advice.thanks.

  • O2 Sensor Heater Circuit Malfunction - Bank 1 - Sensor 1
  • Basically the ECM Electronic Control Unit has determined your O2 sensor is taking to long to begin reacting properly.
  • The causes could be
  1. O2 heater element resistance could be to high.
  2. An internal short or opening in the heater element.
  3. O2 heater circuit wiring with high resistance.
  4. Open or short to ground in the wiring harness.

  • The fixes are
  1. Check the harness and connector to the O2 sensor for shorts or ground.
  2. Replace that O2 sensor.

  • Bank 1 sensor 1 location for this vehicle is located on the exhaust manifold back by the firewall on top of the manifold..
  • Thank you for using FixYa

Regards, Tony

Jun 19, 2011 | 2002 Dodge Grand Caravan

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Where is the oxygen sensor bank 1 sensor 1?

From the 2002 Oldsmobile Alero manual:
A device found in the exhaust manifold, which generates a small voltage dependent on the amount of oxygen present in the exhaust stream, used as a signal to the engine-control computer to determine the amount of fuel necessary to maintain a proper air/fuel ratio.
What this means to me is search the exhaust manifold for it - its screwed into it.
Unscrew it with a specialty oxygen sensor socket (a slotted 7/8-in hex socket) - available for
$10 at any parts store. This is likely the HO2S (heated oxygen sensor) Bank 1 Sensor 1, since
it is before the catalytic converter, the second oxygen sensor (Bank 1, Sensor 2) should
be the one located after the catalytic converter.

P0130 - HO2S-11 (Bank 1 Sensor 1) Circuit Closed Loop Performance
P0131 - HO2S-11 (Bank 1 Sensor 1) Circuit Low Input
P0132 - HO2S-11 (Bank 1 Sensor 1) Circuit High Input
P0133 - HO2S-11 (Bank 1 Sensor 1) Insufficient Activity
P0135 - HO2S-11 (Bank 1 Sensor 1) Heater Circuit Malfunction

Note the P0131 can be also be caused by a bad MAP (Manifold Absolute Pressure) sensor,
so yank the MAP sensor and check the computer for a lean fuel condition (P0131=low input).

Mar 24, 2011 | 2002 Oldsmobile Alero

3 Answers

Where is o2 sensor 1 located on a 2002 aztek any help would be greatly appreciated

Which one? Your vehicle is equipped with 2. One is in the exhaust manifold on the left bank and the other is in the exhaust pipe after the catalytic converter.

NOTE: Most O2 sensor codes do not mean that the O2 sensor should be replaced. Most of the time, the O2 sensor is only reporting the failure of one of the other system components. To save time and money, I personally recommend having the vehicle diagnosed by a qualified service technician. I have seen many people spend hundreds of dollars on O2 sensors only to find out that the problem was caused by something else. Case in point: One man spent nearly $500 replacing all 4 of the O2 sensors on his Ford F-150 Pickup only to have the O2 Sensor code return 2 days later. He brought the vehicle to me and I fixed it with 50 Cents worth of vacuum tubing. O2 sensors do fail, but about 70% of all the O2 sensors that get replaced do not fix the problem that caused the O2 Sensor fault code. Fault codes Never tell you what parts to replace. They only tell you which of the many parameters monitored by the computer is out of specification. Proper diagnosis is required to find out why.

Jan 15, 2011 | 2002 Pontiac Aztek

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O2 sensor location for 2002 Ford Focus Sedan . Have replaced 1 of the O2 sensors in the engine carpartment but won't reset and I also understand there are 2 other O2 sensors that maybe causing them to not...

to make you clear where does the oxygen sensors where is........... some have four, three or two, all O2 SENSORS ARE LOCATED AT EXHAUST PIPE. before and after catalytic converter,

Jul 31, 2010 | 2002 Ford SVT Focus

1 Answer

I have 2002 mitsubishi montero sport 3.5L with a check engine code for O2 sensor no circuit activity Bank 2 Sensor 1. Any Help?

replace the o2 sensor the one before the cat converter with a quailty sensor like a denso brand o2 sensor

Apr 08, 2010 | 2002 Mitsubishi Montero Sport

1 Answer

My car indicates check engine sigh with following two codes 1: p0139 2: p0140

Hi Garcha,

Both codes relate to O2 Sensor # 2

Code P0139: O2 Sensor Circuit Slow Response - Bank 1, Sensor 2
Code P0140: O2 Sensor Circuit No Activity Detected - Bank 1, Sensor 2

A faulty O2 sensor will mean incorrect signals will be sent to the EFI computer, causing erratic engine running.


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Jan 27, 2010 | Hyundai Motor 2002 Elantra

1 Answer

O2 Sensor problem

this pic with be the fix ya

Apr 10, 2009 | 2002 Toyota RAV4

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2002 Pontac Grand Prix GTP P0171 code engine stumbling at times

Bank 1 is the frt side exhaust manifold (did they say bank 1 sensor 1?),you can start by replacing that sensor,i would check the intake for leaks ,the gm 6cly. are known for bad intake gaskets,you will see oil coming out form the frt or rear of the intake,also check your atifreeze overflow bottle for bronwish sludge,which means that the oil is mixing with the antifreeze.A leaking intake could cause that lean condition.

Mar 29, 2009 | 1998 Pontiac Grand Prix

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