95 540i needs new Catalytic Converter(s)..

[Chicano91]

Was having trouble doing my emissions test. Have had a shop take a look at my car and see why it would not pass and said that my Catalytic Converters are bad. Was told it was very expensive and was advised to go aftermarket and do it at a cheaper shop or do it myself. Since the shop said converters I imagine there are 2 I need to replace. I'm I correct in saying that there is two of them in my car? Anyways anyone know where I can find these parts for cheap? I am looking for the cheapest possible just to pass emissions. Is this something I can fix myself? If not what labor charges could I be looking at for this? My tags expired on the 30th. Cant park it in my apartment cus I am scared of it getting towed. So I have to fix this soon and in the mean time get it out the shop in the next few hours and maybe garage it til then.

[ShapeShifter]

Should have had your car tested before beginning of april not the last day....

Yes you have two convertors. Take the car to a muffler shop and they should be able to have them both replaced for under $500.
Unless you can weld, your out of luck.

Did the shop tell you why the converters are bad or are they just going on a hunch?

[Offtopic]

Order some from Jegs.com (http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&Ntk=all&Jnar=0&Ne=1%2B2%2B3%2B13%2B1147708&searchTerm=Catalytic+Converter). They sell for around 100 a piece. That'll keep you under 300.

[Chicano91]

I am going to go in today and ask them why they are bad then. Its a very reputable shop and they do a good job of informing you of the problems down to the last detail. Once I get the info I will post that here. I tried getting my car tested but the pedal broke(the kickdown switch and something else) and the car was not able to maintain the speeds for an emissions test. Luckily was only an 80 dollar fix but I have been trying for the last two weeks. Did not have the money at the time so I was stupid and waited this long. I only have had the car for a little over a month and it was at the shop for various other reasons before then so I had to get to everything slowly. I was thinking under $500 as well. Yet I fell like maybe going after market and trying for a $300 price instead if possible. Think that could be a realistic budget? Anyways any websites you can recommend to find them? Also I can weld if need be, have an uncle with an hvac company that has various tools for those jobs. Yet I do think I might as well get it done in a shop.

- - - Updated - - -

Okay I went to get my car and on my invoice it said "Catalytic convertors advised for NOppm".

[mottati]

the under $500 is for aftermarket, oe bmw cats will be more in the $2k range. Many things can cause high NO, specifically high combustion temps. Is the car otherwise running well? No air/vacuum leaks, proper thermostat etc?

[Chicano91]

@mottati - Yea that price is what makes me look for aftermarket. Was told at my shop that the price would be 2.5k otherwise. Anyways the car does not have much problems all this month its been going in and out of the shop to fix any problems. As of right now I have a small oil leak, coolant leak(hose just needs to be cut and refitted), and break fluid leak at the grommets in the master cylinder. After those leaks nothing else is wrong with the car. Its sucks it is very close to passing.. Whats weird is that when I got the car last month I passed the NOppm test with an average reading of 300, and now the reading is 1000.

@offtopic - Thanks for the site. Gonna look at it now...

[K Fox]

the under $500 is for aftermarket, oe bmw cats will be more in the $2k range. Many things can cause high NO, specifically high combustion temps. Is the car otherwise running well? No air/vacuum leaks, proper thermostat etc?


Whats weird is that when I got the car last month I passed the NOppm test with an average reading of 300, and now the reading is 1000.

I'd put money on the fact that you likely picked up a small vacuum leak, just like motatti said. In case you don't know, the M60 is quite sensitive to vacuum leaks, and a small to med vacuum leak will cause higher NOx readings due to the lean running condition. I can't say it's not your cats for certain, but I'd seriously check for vacuum leaks before replacing them - I just passed emissions with flying colors on my 6 speed with over 273k miles on it and the stock cats. And that on Colorado's new system that is even tougher now than Cali's is (I used to be in Cali - I know how they do it). Do a quick search around here for M60 running issues, or M60 idling rough and you'll get lots of good info on what to check out. I'd advise a home brewed smoke test for a cheap definite answer - just need a small fog machine and a little time. If smoke comes out anywhere on the intake system, that's a leak and will skew the readings. But seriously, you don't want to replace the cats and still fail, which can easily happen if they're not the root of the issue. Plus, your stock cats are worth some good money via recycling if they're not broken up - but the shop is going to press really hard to keep them for that very reason.

TL;DR Basically, you need to make sure it's not a vacuum leak before wasting money on cats.

Fox

[Chicano91]

Once again K Fox you come with good sound advice. Even though I was to late to read it -_- I just ordered the cats (MagnaFlow 94005). I will check for leaks though. If anything turns up and the cats are fine I can just sell the Magnaflow's on Ebay or find out if I can return them.

[K Fox]

Eh, as long as you don't have them installed, you should be able to return them. But definitely make sure your cats are bad before installing them - the aftermarket cats are OK, but simply aren't up the the standards of the stock ones, and will not last as long. If they're not broken up inside, the stock cats on these cars are phenomenal. Huge suckers...and apparently last a long time.

Fox

[Chicano91]

K Fox I did have a misfire and after searching older threads I have read that misfires can damage the cats. I bought my car with a misfire and drove it for a bit from shop to shop in a two week interval until I got it fixed. My car used to smell bad of burning gases. Maybe that info might give the reason why I might have bad cats.

[nonturbodan]

Misfires will kill the cats very quickly. A bad plug or coil will do it. Burning oil will cause harm as well, but more gradually. The owners manual does state that if your check engine light comes on that you should drive the car immediately to a BMW service facility while avoiding hard acceleration or high engine speeds. Its that easy to kill a cat with a dead cylinder. Later engines such as the M62 with OBD2 and misfire detection will shut off fuel to a misfiring cylinder, but the M60 does not have that capability to my knowledge.

[slickbeamer]

if anyone replaces their stock cats message me i'll buy the old ones for good money :)

[84318i]

I wish I could use MagnaFlow 94005, these are CHEAP! (but since they aren't CARB legal, we can't use these in CA).

[yuceturk1453]

Which state do you live? Many states do not do emission anymore. I have bad cats, and I live in NJ, never had any problems.

[Chicano91]

I ended up getting only one cat replaced. I already had a mangaflow installed and one stock. The magnaflow is the one that had gone bad and my stock was still good. In all only 140 for labor and 73 for the cat from summit racing. Passed emissions with flying colors. With that done now I will be definitely keeping this car. Anyone think it might be worth a restore? Has rust on the panel next to my gas cap/door. No other rust though..