[KeithO]

My wife's car (1995 BMW 525i) has been slowly losing power and having reduced fuel economy over the last 18 months. I rarely drive the car. 2 years ago, it got about 32mpg on highway trips. Yesterday, I drove it for about 150 miles and only got 25-26mph.

It is down on power and very occasionally smells like a morning-after Guiness-fart. I am 90% sure that the cat is shot. I priced OEM replacement cats and every source I checked was in the $485-$500 range (yikes!). There is also the obvious choice of getting a universal cat and making it fit...

How can I be absolutely sure that this cat is bad? I'd like to be completely sure before I commit the time and potential effort on this.

Thanks

[bruecksteve]

I just did that to mine. It rattled for along time (all the pieces floating around inside) until one day, the car had NO power and it sounded likeit was hissing.

We dropped the cat-back pipe and found a huge piece of cat gut blocking the exhaust pipe. We took a big air chisel and broke all the pieces up, started the car and blew it all out. That fixed it!!!! Sure sounds much better with my Hooker cat-back too!!!! I'm taking it to have it inspected for emissions soon, we'll see if it passes. I understand that sometimes it does, sometimes it doesn't.