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Old 03-13-2006, 01:51 PM
coelacanth's Avatar
coelacanth coelacanth is offline
prehistoric bony fish
Location: Santa Monica, CA
Join Date: Jul 2005
Posts: 385
Mein Auto: 1997 Arctic Silver 540i 6
Originally Posted by Lscman
Hope that check wasn't done based upon my expressed concern. Ventilation problems can be diagnosed by removing the dipstick and checking for pressure with your finger. The whole ventilation system can be rebuilt by a reputable dealer for $500. What the heck did you get for $1500??

Your service advisor at Bob Smith is a smart guy. If you choose non-OEM cats, he will not be able to profit. He is milking you dry with his recomendations.

I would advise you to purchase a set of used cats from some M5 gearhead that put race cats on. The going rate on ebay and elsewhere is $400, but you need to confirm the reason they removed them. Plan B is aftermarket and plan C is overpriced OEM. Search for posts about good aftermarket not just buy anything or service engine lights and failed tests can result.

You can not run a car on bad cats for long. Once they quit working, they begin to clog. At some point, the backpressure will destroy your cylinder heads and a $8K motor replacement will be needed.
Thanks for the input. I had them check the ventilation system because I started hearing a howling sound coming from the engine a few months ago and got advice here on the Fest that it could be the PCV valve.

Here's my car:
1997 540i-6
120K miles
Dealer says that the cat on bank 1-4 may have been replaced before. I thought that $1,515 was a bit steep as well, but Calabasas is a pretty affluent area, and people around here just say yes to whatever their service advisors tell them. Each labor unit at Bob Smith is $120...outrageous.

Is there a way that I could tell if it's the cat or O2 sensors that are bad?
I think I'll end up taking your ebay advice, getting a new cat and having GT International, an indie shop in Los Angeles that I've heard good things about, install it.
$503 shipped for new OEM cat is all I could find. I hear it's about an hour job. So I guess I'm looking at about $600.

When I told my service advisor that I'd have the cat fixed elsewhere, she said, "Oh I was talking to the tech and he thinks that you probably found someone else to do the job for about half as much as we charge". I looks like it'll be less than half. =)

DOH! I just realized that the ebay cat is not legal in California. Bavarian Autosport has cats for $409.95, but the ones that are legal in Cali are $929.95 each.

I guess it's time to start cruising BMW boards to try to find someone in Cali who replaced theirs with an aftermarket cat.

Last edited by coelacanth; 03-13-2006 at 02:19 PM.
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