Exhaust: the manual's a liar

[losdiosdeverde86]

99 LGT Limited - 50k Miles - Sedan - Auto

So, my exhaust broke. What do i mean by 'broke'? well, the middle of the mid-pipe (specifically the resonator) complete broke off.

My problem is that I don't know what I need to replace. I could definitely use some assistance. Please check out the exhaust diagram (i made) below.

Figure A: What my car originally had
Figure B: The greyed out dashed line is what broke off
Figure C: The FSM diagram

https://sl-i.net/FORUM/images/imported/2009/07/exhaust-1.jpg

Notice Figure A has 3 cats, and Figure C has 2 cats.

Can someone shed some light on this?

(yes i'm sure mine has 3 cats, yes i'm sure i'm looking at the correct manual)

[rougeben83]

probably california emissions car? Look for that. 3rd cat is post 2nd o2 sensor, not really there to affect the ecu, just to clean up for the sniffer.

Also, it looks like the midpipe's resonator fell off, you can have that rewelded...

[losdiosdeverde86]

probably california emissions car? Look for that. 3rd cat is post 2nd o2 sensor, not really there to affect the ecu, just to clean up for the sniffer.

Also, it looks like the midpipe's resonator fell off, you can have that rewelded...


Yeah, the CA emissions idea is something i've been researching.

It makes sense.

Also, there is no O2 sensor (you're correct) attached to that third cat, and the car's registered in PA and in PA, only cars older than a 96 take the sniffer, the rest are OBDII checked.

So, bonus.

If I can get a couple other people to concur with you then i'll be saving myself a good 500 bucks.

[impreza_GC8]

Have an exhaust shop weld it up, you don't need the resonator there. This same thing happened to my mom's '97 Outback. Cost about $100 at an exhaust shop to have it fixed up. Don't think any more into it, its an easy fix.

[97legacyGT2.5]

I had a 3rd cat on my car as well. I looked up the exhaust in a stock replacement (Gorlicks and AP Exhaust) catalog and the stock replacement didnt have the 3rd cat, just the resonator. Dont worry about it, like impreza_GC8 said just have a local exhaust shop weld in a new section, or if you want after market muffler and mid pipe just have them bend and weld up an entire new cat back section (thats what i did) :grin:

[Huffer]

Custom midpipe time. Done.

[decke48]

the "third cat" isnt an actually cat, only a glass pack to help further on sound, it doesnt madder which one you get unless your in cali and need it, so you can get either and it will be fine

[2.5GT]

Exhaust shop can easily weld an aftermarket resonator back on. Or get them to make you a resonator-less mid pipe :grin:

[Benfolio]

My GT had what figure A looks like, but it was just two resonators. No cats. Wagon had figure C.

Now it's got the rallitek/borla midpipe, but I agree a custom straightpipe would be perfect and much cheaper than a factory or replacement piece.

[rudgers73]

probably california emissions car? Look for that. 3rd cat is post 2nd o2 sensor, not really there to affect the ecu, just to clean up for the sniffer.

Also, it looks like the midpipe's resonator fell off, you can have that rewelded...

My car was originally purchased in Michigan, assembled in Indiana, and it looks like figure A. Yes, the 2nd cat has the rear O2 sensor, but I don't think there is a state-specific difference in the exhaust on a 99 Legacy as far as cat 3 or no cat 3. Maybe it was an inter-model-year iteration?? "Beta" if you will. Although, I have never heard of anyone having something that looks like Figure C in my experience, only Figure A.

I currently have a crack in between Cat 1 and 2 (damn it) so I am going to have to weld it instead of delete unnecessary things that make my car quiet and smell nicer. What a pain

[rougeben83]

probably california emissions car? Look for that. 3rd cat is post 2nd o2 sensor, not really there to affect the ecu, just to clean up for the sniffer.

Also, it looks like the midpipe's resonator fell off, you can have that rewelded...

My car was originally purchased in Michigan, assembled in Indiana, and it looks like figure A. Yes, the 2nd cat has the rear O2 sensor, but I don't think there is a state-specific difference in the exhaust on a 99 Legacy as far as cat 3 or no cat 3. Maybe it was an inter-model-year iteration?? "Beta" if you will. Although, I have never heard of anyone having something that looks like Figure C in my experience, only Figure A.

I currently have a crack in between Cat 1 and 2 (damn it) so I am going to have to weld it instead of delete unnecessary things that make my car quiet and smell nicer. What a pain

From your diagram it looks like there's a 3rd cat. It may as well have been another resonator. "California emissions" was a very common no-cost option (and standard in cali of course) that some cars came with during the 90's because california had stricter emissions/ehxaust requirements than the rest of the country and manufacturers found it easier to make a seperate set of emissions gear for that state rather than making every car conform to those stricter reqs. Of course this is irrelevant now as federal emissions standards have come much more stricter, mirroring california.

Either way, it's no big deal to fix. Just take it to an exhaust shop.

[losdiosdeverde86]

i'm going to try to temporarily fix it today with a piece of flex pipe until i can take it back to my old garage in pittsburgh and have it replaced properly. i'm just going to get a straight pipe for the permanent fix.