DIY: N51 SULEV EAC sensor replacement (cheaper than OEM)

[MINIz guy]

I have an 2008 128i that is past it's 15yr/150k mile SULEV warranty. It popped up the P0143E/2AD8 code, which related to the EAC sensor going bad. Now, BMW's only option to fix this code is a $500 OEM radiator. Here is how I went around it.

Part 1: I describe my problem, and show you how the EAC sensor comes off the stock radiator.

Part 2: I install a new EAC sensor using the proper procedure (I followed ALLDATA). So far, no new codes after a couple drives.

Sensor part number I used was: Mercedes 2219055600. There are other sensors available, which supersede this part number.

Glue I used: Palm Adhesives 155 LT, an alternative to Loctite 4204

If replacing the entire radiator too, purchase the CSF 3718 radiator. You will still be cheaper than the OEM BMW unit, and have a refreshed cooling system. This is the only aftermarket radiator that has the block for the EAC sensor.

[chalupa2000]

Thanks for posting this any updates as to how it's working? Appreciate the huge savings for the sulev crew

[MINIz guy]

It is now 2k miles later and no issues. I've even had to clear all readiness monitors for a VCG change and it reset everything fine.

[MarinerZ4C]

My car is a 2008 128i with the same wonderful radiator design. I have had EAC code pop up. I cleared it, and a week later it came back. The radiator is fine, so I followed your thread. Thanks, MINIz Guy !

When I ordered a similar BEHRU temperature sensor from a MB dealer online, they contacted me back and asked for my VIN. I explained that I don't have a MB vehicle, but that the manufacturer of my car makes me buy the entire radiator instead of just the part. I said using the MB part was a known repair. The lady's response was "Oh, got it !" and said my part would be here in a couple of days - which it was. I could not find exactly the P/N that MINIz Guy used, but I think the P/N differences are mostly for cable length and connector style. My P/N is 221 905 56 00 A

I add a photo, because I may have discovered why I got an intermittent error. Notice that my sensor popped off the radiator almost intact, and I could see the failed glue still in the radiator block. Maybe this made the temperature response slower, or maybe this had nothing to do with it, but it's all back together, and I will report my experience.

[MarinerZ4C]

N/M

[abytheone]

I have 328i coupe 2008 model which I purchased in NY. Currently, I live in VA. My SES light has been intermittently turning on. Last year it has been on constantly. The dealer suggested to pay $200 for full diagnostics to which I complied. During this, I came to know about faulty EAC sensor. Consequently, the car could not pass the emission inspection. As a result, I was not able to get the registration of car renewed.

I came to know that the EAC sensor cannot be replaced, and to fix it, the only option is to replace the radiator which cost $600 parts alone!! The total cost of repair for that alone would be around $1000. This was a tough spot for me.

Researching further on this forum, I came to know what EAC sensor is all about . I came to know about SULEV and that people were successful in getting it replaced free of cost. https://www.bmwcca.org/forum/index.p...6/#post-107566

Subsequently, I decided to take my chances and went to my dealer in VA. As anticipated, the service technician wasn't aware of SULEV and 15/150K warranty on Super Ultra Low Emission Vehicle parts. After he realized that I had done extensive research and I knew what I was talking about, he tried to discourage me, he said that since my car is in VA, it would not be covered as SULEV 15/150K terms are for vehicle in certain NE states and CA.

I pushed harder and requested to talk to the service manager. She was understanding. I showed her the SULEV terms and condition from official BWM handbook that came along with the care wherein its clearly written that SULEV warrant applies to car "sold, leased, and/or registered" in NE states and CA. Since, my car was purchased in NY, hence as per terms and condition my car registered in VA should still come under warranty.

She finally called BMWNA and they authorized that the repair should be covered under SULEV agreement.

The dealer would need to work on my car for few days and confirmed that they would do every repair related to SES if it were due to parts covered under SULEV repair warranty /SULEV performance warranty.

Thank you.

[djacinto]

Just wanted to update this thread. I installed a csf radiator about a year and a half ago, and in that had to transfer over my eac sensor. I also had an issue with it being stuck in the old one, and was able to transfer over the probe and glued it down with loctite 4204.

today however, the cel came on, what i initially thought might be a misfire since it's the first cold day here in texas, was in fact the eac sensor falling off the rad. I have code 2ad8: eac sensor, monitoring. in this scenario since the probe had already broken, i will inspect it but likely install a mercedes one.

additionally, i got a catalyst conversion 2 29f5 code, so unsure if they are tied together

will update once job is done

Update: I zip tied it back on and it’s working so far