[Senilsson]

Hello,

I have bought a 2012 X3 with the N52 engine that has 89k miles on it. (Long thread of me looking for the right car here https://x3.xbimmers.com/forums/showthread.php?t=1766984 )
It is sold from a reputable dealership with good reviews.

I was going to pick it up tomorrow but they told me that the catalytic converter needs to be replaced for it to pass emissions.
My first thought was positive, they're actually fixing what's wrong with the car but at the same time I can't help but wonder what caused the catalytic converter to go bad. You would think some sort of fuel or ignition problem would cause this?

The salesman says he doesn't understand much and just promised the mechanic would make sure the car is 100% for me (again, whatever that means)
I'm trying to get the number to the mechanic or the service manager to find out what's going on but in the meanwhile I would really appreciate your feedback!

[Wgosma]

This CAT issue would lead one to conclude the dealer did not go thru the car and do a thorough inspection of its condition after acquiring the vehicle. I'd be very wary of taking ownership of this car- I presume the seller is not providing any type of warranty for the car (?)

Without knowing anything more if I was in your place I'd use this CAT issue as reason to pull the plug on the deal, now. Seems a risky buy, you don't know what other issues may crop up after you take ownership. if there is no warranty beyond the new CAT converter, you're in potentially risky situation going forward.

This situation is why it's recommended to have an independent shop do a pre-purchase inspection.

Good luck/Bill

[frisbeeguy]

eh...this is where the call to buy becomes iffy imo.....but maybe someone else here can give better input.
I usually avoid vehicles that need a cat replacement, especially vehicles with the N52 engine...it can either be truly defective or lack of maintenance....but live data is generally the best assessment on overall engine condition.
Link: https://www.shadetreegarage.com/blog...tic-converter/
Another link: https://www.vipermotorsports.com/Abo...he%20converter.

Basically there's a high chance of lack of maintenance. When I picked up my X3 this year, I look for the least amount of fixes to do...in my case it was just tires and dealer replaced the tailgate control module. Rest was fluid maintenance.

[e30lover318i]

Cheap fix is to put a “spark plug defaulter” in ..normally what happens is over a period of time the vehicle detects a cat efficiency issue due to a “worn catalyst” this is very common on the e90 chassis with n52 motor. The defaulter or oxygen sensor spacer pulls the sensor out of the flow to trick it into thinking it’s efficient. This is basically what people or companies do for the catted down pipes on the turbo motor, I’ve done a lot of cars with the spacer method but this boils down to your preference... some people get upset because it’s technically damaging to the environment... but any pre obd2 car is damaging the environment if you want to get technical as it’s not as efficient as the newer vehicles... hopefully this helps you I would highly suggest the spacer but you will need to find an Indy shop to do this for you as a dealer will NOT due it for liability reasons

Edit sorry didn’t read they are fixing it for you, please look into the n52 power e90’s for more info very common issue. Please be cautious with aftermarket cats sold to independents for example dorman has lower quality cats that dont always hold up

[pungo]

Generally, a failed cat is caused by unhealthy motor conditions for a long period of time. It could be anything from worn out spark plugs not providing a clean burn, to excessive oil passing through cylinders. It's very rare for a cat to just fail without an engine issue. Sure maybe after 250-300k miles, but not at less the 100k.

I'd ask if they're replacing the cat with a genuine BMW one or aftermarket.

[Senilsson]

Thanks for all the replies guys, it's really helpful!
When I spoke with the tech just a few minutes ago he couldn't disclose the entire repair information, but he promised they could do so when I pick the car up on Saturday.. I'm going to talk to the salesman soon and ask to have that information today instead so I can see if it was OEM parts or something else.

Isn't it amazing that this was brought to my attention after I made a non-refundable deposit..

[Senilsson]

Ok, I talked with the manager now and he apologized and said that the salesman had prematurely shared information he didn't fully understand (on his day off) - there was no CEL or problem with the car, they did find a code on an O2 sensor that's being replaced so that the car will be able to pass emissions here in IL.
I'm at least calmer but they said they would send the documents from this indy shop once it's done.

[ItsmeX5]

The code on the o2 sensor would throw a CEL if I’m not mistaken. It’s been a while since I’ve worked on a bimmer, but on my benzes a failed o2 will throw a CEL.

[Wgosma]

Originally Posted by persianamir

The code on the o2 sensor would throw a CEL if I’m not mistaken. It’s been a while since I’ve worked on a bimmer, but on my benzes a failed o2 will throw a CEL.

think you're correct, most any component fault that is related to emission system will yield CEL.

[Senilsson]

Maybe it was a historic code? I will make sure to get the paper work when it leave the shop.

[ItsmeX5]

Originally Posted by Senilsson

Maybe it was a historic code? I will make sure to get the paper work when it leave the shop.

A historic code wouldn’t cause them to change the o2 sensor to pass emissions...if an o2 sensor was replaced at 80kish miles it would not be a concern for neglect. The issue that other people raise in regards to the dealer telling you this after you put a deposit is the only issue there.

Either way, I just picked up a 2012 with 80k miles drove it 1600 miles round trip and I love it! Purchased new fluids for trans, spark plugs, cabin air filters, and a tie rod that is giving a little play but I love the car. Don’t think you’ll be disappointed. Good luck and keep us posted

[Senilsson]

Originally Posted by persianamir

A historic code wouldn’t cause them to change the o2 sensor to pass emissions...if an o2 sensor was replaced at 80kish miles it would not be a concern for neglect. The issue that other people raise in regards to the dealer telling you this after you put a deposit is the only issue there.

Either way, I just picked up a 2012 with 80k miles drove it 1600 miles round trip and I love it! Purchased new fluids for trans, spark plugs, cabin air filters, and a tie rod that is giving a little play but I love the car. Don’t think you’ll be disappointed. Good luck and keep us posted

Ok, yea I totally agree with you. This whole buying experience went from exciting to a daily frustration. Thought that going to a dealer would save me some headache but obviously not, lol... Just 2020 I guess.

Congrats on the car! Hope I'll be happy.. More to come for sure

[Wgosma]

In USA Car dealerships and car salespeople in particular unfortunately have a pretty sour reputation with the motoring public, not that there aren't good Dealers and Salespeople, but they seem to be too few and too far between.

I'm age 69, the last time I bought a car from a dealer was in 1991; since then every car has been a private party buy from original owner- clearly this way of buying is not for every car shopper; few are able/willing to take the time for this, and buying used always means some compromise in equipment, color, no warranty, etc. it's worked well for me, never been burnt going this route and have been able to find car equipped close enough to my needs and desires, but it takes time.

[BIG_KID]

I wouldn’t believe anything the dealer tells me....

[Senilsson]

Originally Posted by BIG_KID

I wouldn’t believe anything the dealer tells me....

You and me both.. The only thing being replaced according to them is an O2 sensor but we'll see what the invoice says. It's been at an indy shop and not their own shop.

[Senilsson]

Ok so it has been a wild ride. I got the car delivered on Friday last week at 6.30PM and my first child was born a measly 10 hours later. Good thing the car came when it did, the hospital is only 10 minutes away but having a car is a hell of a lot more convenient than taking a cab.

Anyway, haven’t had a lot of time to check the car out but it is good so far. Paper indicated a code on the O2 sensor and that’s also what has been replaced so I’m just gonna hope that’s it and all is good.

[ItsmeX5]

Congratulations on the baby and the car. Best of wishes to you!

[383vett]

Wow, good news all around. Congratulations 2X.