[markm1162]

Hi, I have a 2003 325i (M54) that is in need of new O2 sensors or at least that's what our shops computer is telling us. I've been looking around for O2 sensors and I cannot believe how expensive they are! There's a little luck on my side that I am the IT manager of a repair shop and have access to wholesale pricing on the sensors but they still range from $117-$150. I purchased this vehicle in May 2016 with 157,000 miles on it now has 190,000 miles on it. I only paid 3K for the car but I have put a battery, water pump, fuel pump, expansion tank, NGT spark plugs and a new set of tires and a few other little things. More or less I have ironed all of the kinks out of this vehicle but I'm having a really hard time digesting a cost of $600 plus installation that would turn out being over 1/6 of what I paid for the vehicle not to mention the high mileage.

I did find a company called Kwiksen on Amazon that sells O2 Sensors https://www.amazon.com/Kwiksen-234-...automotive&vehicleId=1&vehicleType=automotive

But these are for a 325xi and I'm not sure if they'll fit my vehicle or not. I'm pretty sure the O2 sensors have not been changed in this vehicle but I'm not certain of it. I will mention that I also run nothing but premium gasoline in this vehicle and do full synthetic oil changes every 6875 miles. I'm not opposed to buying used but that would probably be from someone in this forum to possibly has a salvage/wrecked BMW with lower mileage that they would be willing to sell these sensors from.

Here is a link to the parts that I need as listed on realoem.com
http://www.realoem.com/bmw/enUS/showparts?id=ET37-USA-03-2003-E46-BMW-325i&diagId=11_2181

Any input or advice is appreciated!

Thanks,

Mark_a_

 

[markm1162]

Sorry this is the right link to the sensors $215 per unit according to them. Ouch!

http://www.realoem.com/bmw/enUS/showparts?id=ET37-USA-03-2003-E46-BMW-325i&diagId=11_3555

 

[MTX-4]

You only need the two pre-cat O2 sensors really.

Check this : https://www.amazon.com/Bosch-13477-...?ie=UTF8&qid=1486539877&sr=8-1&keywords=13477

 

[irdave]

Yeah, u/jfoj helped diagnose mine being the issue- I think I got them at Napa for very affordable. Those and a new MAF were the cheapest 10 or 15 hp I've ever seen...

 

[jfoj]

Need to be careful here, the OP has a 2003, we need to know the build date or if the car has a 3 or 5 wire MAF.

There could be 2 different Pre-cat O2 sensor options. There are the standard 4 wire O2 sensors and the 5-6 wire Wideband O2 sensors. The Wideband O2 sensors are close to $100, the non Wideband O2 sensors are around $40 each.

There are also a few different Post-cat O2 sensor options as well. More on this below.

Given the age, mileage and what the OP paid for the car, the car likely has original O2 sensors. The Post-cat may or may not need to be replaced at this age. If the the car is having problem clearing the O2 Sensor and Catalyst Readiness Monitors the Post-cat O2 sensors will need to be replaced.

Early 2003 with the 3 wire MAF required 2 - Bosch 13477 Pre-cat O2 sensors for around $40 each

https://www.amazon.com/Bosch-13477-...446&sr=8-1&keywords=bosch+13477+oxygen+sensor

Later 2003 with the 5 wire MAF require 1 - Bosch 17215 and 1 - Bosch 17216 Pre-cat O2 sensors around $105 each

https://www.amazon.com/Bosch-17215-...045&sr=8-1&keywords=bosch+17215+oxygen+sensor

https://www.amazon.com/Bosch-17216-...084&sr=8-1&keywords=bosch+17216+oxygen+sensor

Post-cat O2 sensors for cars with a 3 wire MAF, the car will require 2 - Bosch 15109 for around $60 each

https://www.amazon.com/Bosch-15109-...227&sr=8-1&keywords=bosch+15109+oxygen+sensor

Post-cat O2 sensors for cars with a 5 wire MAF, the car will require 1 - Bosch 15680 and 1 - Bosch 15681 O2 sensor for around $90

https://www.amazon.com/Bosch-15680-...447&sr=8-1&keywords=bosch+15680+oxygen+sensor

https://www.amazon.com/Bosch-15681-...487&sr=8-1&keywords=bosch+15681+oxygen+sensor

You want Bosch Direct Fit O2 sensors if you do not want headaches, use this Bosch Online Application Guide as a reference - https://www.boschautoparts.com/en/auto

I can tell you a few things, you can shop your local auto parts store using the online purchase, you can often find online coupons for discounts for online orders and then pick the parts up in the store. Check ebay and hope the seller has non Asian counterfeits and also check RockAuto and other online Auto parts vendors.

I expect the non wideband Pre-cat O2 sensors on Amazon at $40 is about as cheap as you and find them. Wideband Pre-cat O2 sensors for around $90 is about the best price you are going to find.

Post-cat O2 sensors for the 3 wire MAF engines you may be able to find closer to $50.

Post-cat O2 sensors for the 5 wire MAF engines you may be able to find closer to $75. You can also use the cheaper of the 2 Post-cat O2 sensors on both sides, the only difference is the color of the insulation, as long as you keep the sensor wiring and connectors straight, the color of the insulation does not impact performance.

 

[markm1162]

The build month is 03/03 (March 2003)

 

[jfoj]

The build month is 03/03 (March 2003)

My notes are "from 03/03" the car should be configured with Wideband O2 sensors. BUT, before you order anything, just check to see if the MAF has 3 or 5 wires, a 5 wire MAF means the car has the more expensive Wideband O2 sensors.

Wideband sensors seem to last a bit longer than non wideband sensors from my experience. What problems, if any, are you trying to sort out with O2 sensors?

You stated " is in need of new O2 sensors or at least that's what our shops computer is telling us".

Forget about what the "shop computer" is telling you. I NEVER find any O2 sensor failures other than O2 sensor heater failures on any tools or software.

If you have specific Pxxxx trouble codes and Freeze Frame data, lets start with this. Also what is the "shop computer"??? Make, model and are you using the "OBDII" or "Scanner" section of the tool??

I would bet the problem(s) you are having are not due to O2 sensors.

 

[markm1162]

Matco Maximus 2.0 (v49.40) is what we use for the shop computer. I guess originally what brought all this about was that I could not run the car on regular (87) gasoline because the car's engine would cut out at every stoplight. Using premium unleaded fuel fix that problem. However, I'm still getting the Service Engine Soon light coming on intermittently. Sometimes it goes off by itself, other times it will just go off after I reset the fault memory. I am getting 3 main faults upon doing a quick test (sorry I don't have the more specific detail about these) but they are as follows.

1. ECM (Engine Control Module DME/DDE) (2)
2. EWS (Elec immobilize system) (1)
3. IC (Instrument Cluster) (1)

There is another one I also get time to time - LSZ/LCM (Light Switching Center) Fault | 2

 

[jfoj]

OK, now the picture is getting clearer. :facepalm:

1. Forget about the premium fuel fixing anything, it does not work this way, this did not solve any problems with your car.

2. You are making the fatal mistake with the the Matco tool that many "Pros" make. :banghead: You are using the "Scanner" portion of the tool, DO NOT USE THIS FOR DRIVEABILITY PROBLEMS!! Use the "OBDII" portion of the tool or better yet, spend about 1000 times less for the OBDFusion App (under $10) and the proper VeePeak interface (Under $20) for you phone or tablet. This way you will ALWAYS have a quality OBDII tool with you in the car.

3. You need to use OBDII so you can get Freeze Frame and warm idle Fuel Trim values.

4. Get the OBDFusion App and proper VeePeak interface from Amazon.

5. DO NOT reset/clear codes until you have captured and saved the Freeze Frame info.

6. Read this thread 5 times - http://forum.e46fanatics.com/showthread.php?t=897616

7. Get the OBDFusion App and proper VeePeak interface from Amazon.

8. DO NOT use the "Scanner" portion of any "Pro" level tool for Driveability problems.

9. Smoke Test the intake and crankcase and fix all leaks, once leaks are fixed, Smoke Test AGAIN!!!!!

10. DO NOT replace any parts until you gather the proper OBDII data, codes, Freeze Frame and Fuel Trim data.

11. Chances are there are vacuum leaks causing most of your problems.

12. The OBDFusion App and proper VeePeak interface from Amazon are less than $30 for both.

OBDFusion for Android is is $3.99.

Android requires Bluetooth -https://www.amazon.com/Veepeak-Ultra-low-Consumption-Bluetooth-Diagnostic/dp/B01N0Q8LN9/ref=sr_1_2?s=automotive&ie=UTF8&qid=1486113911&sr=1-2&keywords=veepeak+bluetooth

OBDFusion, for the iProducts it is $9.99.

Thank me and show everyone in your shop how to really fix cars without $2000-$5000 scan tools!!! :thumbsup:

 

[MTX-4]

Check the O2 sensor connector. The wideband O2 sensor has a very different connector to that of a narrow band O2 sensor.

It happens my E46 was also manufactured in 03/2003 and mine has equipped with the narrow band one.

You could also verify that with the connector on your MAF as jfoj advised, if you have a MAF with three pins connector, your DME is run on MS43 and narrow band O2 sensor. If you have a six pins MAF connector, your DME is run on MS45 and wide band O2 sensor. My bet is your car is running on MS43. But better to be 100% sure.

 

[markm1162]

Okay, I have some updated information as of today and we did conduct a smoke test and found no leaks. There was some talk about a crankcase vent valve possibly not opening or closing but I'm not positive that's even the case. As far as we can tell it looks like the O2 sensor is a wideband because we did check and the MAF does have 5 wires. We also ran some other tests with a different computer and I did take pictures of the screens unfortunately I cannot attach the pictures here but here is the information that we were able to glean off of that test using a Actron elite autoscanner (Not sure of the model):

The last 7 digits of the Vin number on this vehicle are: PD57615 if cross reference information is needed.

P2240 O2S 2/1 Positive Current Ckt Open
Engine speed (RPM) 1545
Calc Load (%) 3.9
Coolant (F) 194
ST FTRM1 (%) 3.1
LT FTRM1 (%) 2.3
ST FTRM2 (%) 0.0
LT FTRM2 (%) 3.1
VEH Speed (MPH) 42
Fuel SYS1 CLSD
Fuel SYS2 CLSD

So according to what we can tell from this it does look like a bad O2 sensor and I was able to find one through our local distributor for $60.19. I still wonder if the crankcase vent valve is going to need to be replaced. There was a kit with 4 hoses that comes with it for around $177 wholesale. I've owned 7 other BMWs and this one has been my favorite so far. I've pretty much decided that I'm going to drive it until the wheels fall off of it so what I'm trying to do here is cover all my bases. Thanks for all your help so far!

 

[markm1162]

One last question

So I found the OBDII Scanner IOS app for $10 - No problem I can buy that in a few seconds and I've already found it and read a little about it in the app store.

On the Veepeak there are several to chose from:
(Three I think - here's two)

https://www.amazon.com/Veepeak-Upgr...86708584&sr=1-1&keywords=Veepeak+OBDCheck+Pro

This one is 28.99

https://www.amazon.com/Veepeak-Scan...eywords=veepeak&tag=e46fanatics_vl_convert-20

This one is 16.99. I have NO problem at all buying the more expensive one if in fact it does provide more and better information. If there's no difference then I'll just get this one and save a few bucks.

 

[jfoj]

So to answer your questions.

1. The P2240 code is a tricky one. It could be due to a lazy O2 sensor, some cars this has been solved with a DME flash update.

Here are the facts:

1. The car is 17 years old and has 190k miles on it. This car likely has the original O2 sensors still installed. It should be ready for its 2nd!!! replacement set of O2 sensors at 190k miles.

2. I have a hard time believing that after 17 years a DME flash is required to resolve a single DTC, if the DME flash is a problem, it would have surfaced a LONG time ago. While the engine could benefit from a DME flash for other reasons, I do not think this is the first step I would take and I am skeptical that the DME flash is the "solution" for this current issue.

Moving forward I would suggest that the Pre-cat O2 sensors be replaced, I would STRONGLY suggest Bosch Direct Fit replacement O2 sensors. I would not suggest cheaper sensors that require you to cut the original connector off and splice it to the replacement sensor. This is just looking for problems.

As for the VeePeak interface, many people have used the cheaper interface with good results and I think the more expensive interface is a newer and more up to date option with a power switch and supposedly better chipsets.

I have not tried this interface, but VeePeak so far has offered very reliable products that I have not heard about any complaints or failures.

In order to attach pictures, assuming you are using a computer and not a phone/tablet, you can use the Paperclip icon in the toolbar above the dialog box. If you are using a phone or tablet, I assume there are options in the App, assuming you are using the E46Fanatics App.

 

[Scuzone]

I just put in $40 ones from rock Auto but that wasn't the problem it was the lower intake boot that looked good but was actually disintegrated in my 05 325 xi change that and the upper boot also if you haven't yet.

I believe the Brand is Densco Parts? Working fine now on codes p0171 and po174

 

[CylonRed]

Sorry this is the right link to the sensors $215 per unit according to them. Ouch!

http://www.realoem.com/bmw/enUS/showparts?id=ET37-USA-03-2003-E46-BMW-325i&diagId=11_3555

Do not use REAL OEM prices to decide how expensive they are. Find out who makes the OE part (Bosch in this case) and then price at several auto parts houses. You will find the prices are much better than the price at REALOEM.

 

[All2kool]

I have no idea if any of my 4 O2 Sensors have ever been replaced but I would venture a guess they are all original to the car. At 135K miles - should i just change them put? I would be in the Bosch 13477/15109 category so the expense is nominal.

 

[jfoj]

I would highly recommend the Pre-cat O2 sensors be replaced at the 100k mile suggest interval, the more cases I deal with, the more I am finding about 98% of these cars still have original O2 sensors installed.

I hold of on Post-cat O2 sensors for many reasons unless they need to be replaced due to a failed heater or problems with the Catalyst and O2 Sensor Readiness Monitors.

But beware, often fresh O2 sensors help find underlying problems, it is not the fault of the new O2 sensors, they just do a better job detection degraded performance.

 

[markm1162]

Well yesterday we installed Pre-Cat O2's Still registering 0.0. Ended up putting the old ones back on. We are getting voltage up to both plugs (not sure if we are getting enough voltage?) I did purchase OBD fusion as requested and this is what I have come up with:

O2 Bank 1 Sensor 1 = 0.00
O2 Bank 2 Sensor 1 = 0.00

I've tried to insert images into this before but all that happens when I click it is that it asked me to enter the URL of your image and I don't have that online anywhere. Otherwise I would have uploaded screenshots From OBD Fusion. I among some of the others I've spoken with seem to think we may have a broken wire somewhere. What voltages should I be getting through the 2 Pre-Cat O2 sensor plugs if we test them on a Ohm meter? Oh yeah, last but not least the Bosch part numbers are 17215 and 17216.

 

[jfoj]

So you need to be VERY careful here.

You are looking at the WRONG PID's for the Pre-cat O2 sensors.

You need to set up and monitor the PID's with this description:

O2 sensor lambda wide range (current probe) (Bank 1, Sensor 1)
O2 sensor lambda wide range (current probe) (Bank 2, Sensor 1)

Wideband O2 sensors tend to have a different Voltage behavior, they tend to center around 1.0 Volts and can jump to close to 3 Volts when decelerating.

If you read the PDF in this thread carefully it will tell you what you need to do and how to get Logs and Diagnostic Reports to me.

http://forum.e46fanatics.com/showthread.php?t=1097893

Before you spend a lot of time, I can almost guarantee you that the replacement O2 sensors are fine and that they are reporting correctly.

Need to gather the data and make sure you are looking at the correct information.

Did you also CAREFULLY look at the connectors on the inside to make sure one side has Pins and the other side has Sockets?? There are MANY, MANY ways to connect the sensor WRONG, even connect the banks WRONG.

You need to get a handle on this, it is not that hard.

 

[DavidValentino]

Need to be careful here, the OP has a 2003, we need to know the build date or if the car has a 3 or 5 wire MAF.

There could be 2 different Pre-cat O2 sensor options. There are the standard 4 wire O2 sensors and the 5-6 wire Wideband O2 sensors. The Wideband O2 sensors are close to $100, the non Wideband O2 sensors are around $40 each.

There are also a few different Post-cat O2 sensor options as well. More on this below.

Given the age, mileage and what the OP paid for the car, the car likely has original O2 sensors. The Post-cat may or may not need to be replaced at this age. If the the car is having problem clearing the O2 Sensor and Catalyst Readiness Monitors the Post-cat O2 sensors will need to be replaced.

Early 2003 with the 3 wire MAF required 2 - Bosch 13477 Pre-cat O2 sensors for around $40 each

https://www.amazon.com/Bosch-13477-...446&sr=8-1&keywords=bosch+13477+oxygen+sensor

Later 2003 with the 5 wire MAF require 1 - Bosch 17215 and 1 - Bosch 17216 Pre-cat O2 sensors around $105 each

https://www.amazon.com/Bosch-17215-...045&sr=8-1&keywords=bosch+17215+oxygen+sensor

https://www.amazon.com/Bosch-17216-...084&sr=8-1&keywords=bosch+17216+oxygen+sensor

Post-cat O2 sensors for cars with a 3 wire MAF, the car will require 2 - Bosch 15109 for around $60 each

https://www.amazon.com/Bosch-15109-...227&sr=8-1&keywords=bosch+15109+oxygen+sensor

Post-cat O2 sensors for cars with a 5 wire MAF, the car will require 1 - Bosch 15680 and 1 - Bosch 15681 O2 sensor for around $90

https://www.amazon.com/Bosch-15680-...447&sr=8-1&keywords=bosch+15680+oxygen+sensor

https://www.amazon.com/Bosch-15681-...487&sr=8-1&keywords=bosch+15681+oxygen+sensor

You want Bosch Direct Fit O2 sensors if you do not want headaches, use this Bosch Online Application Guide as a reference - https://www.boschautoparts.com/en/auto

I can tell you a few things, you can shop your local auto parts store using the online purchase, you can often find online coupons for discounts for online orders and then pick the parts up in the store. Check ebay and hope the seller has non Asian counterfeits and also check RockAuto and other online Auto parts vendors.

I expect the non wideband Pre-cat O2 sensors on Amazon at $40 is about as cheap as you and find them. Wideband Pre-cat O2 sensors for around $90 is about the best price you are going to find.

Post-cat O2 sensors for the 3 wire MAF engines you may be able to find closer to $50.

Post-cat O2 sensors for the 5 wire MAF engines you may be able to find closer to $75. You can also use the cheaper of the 2 Post-cat O2 sensors on both sides, the only difference is the color of the insulation, as long as you keep the sensor wiring and connectors straight, the color of the insulation does not impact performance.

Awesome information !! Thank you JFOJ! I will definitely be ordering soon.

When you get a moment take a look at my OBDfusion logs for me. Thanks
http://forum.e46fanatics.com/showthread.php?t=1121924