dgjks6

God darn. I can't remember why. But I had to. The muffler is not connected to the catalytic converter. But 2 of the bolts are attached to a support bracket that holds up the muffler.

Is the support bracket welded on? Or could you leave it attached to the car and remove it from the muffler?

dgjks6

Ok. Reply to myself. Looking at the parts diagram (I'm riding with my daughter on her way to college) and not the car



You can disconnect the muffler at the cat or at the bracket. Wonder why I picked the cat when I did it.

swingwing

Old muffler removed for hardware transfer.

S-shaped 13mm ratcheting wrench made short work of the 12 o'clock cat nut. Muffler bracket is held to cat by only two of the nuts. Leave one at 4 o'clock alone.

Here's a picture of old muffler and its Fister replacement. Note that you have to transfer the two brackets to the new muffler. It's been a while since I did the install but I chose to remove the rear bracket at the cat. Only two of the cat nuts have to be removed - The one at 12 o'clock is tough, made easier if you have an s-shaped ratcheting wrench. I call it the "wonder wrench."

swingwing

I didn't remove the rear bumper when I did this muffler job, but did later for spark plug replacement. You'll have a much easier time with either DIY if you remove the rear bumper. It's not that difficult to do.

snaphappy

I’m leaning toward removing the bumper. I guess when I’m in there it will become very obvious whether I need to mess with those three cat bolts or not.

swingwing

The "Wonder Wrench" was invaluable in getting that 12 o'clock cat nut off. Don't think I would've needed it had I removed the bumper.
Small point, but as I mentioned the muffler bracket is attached to the cat on only two of the studs. You don't need to mess with the third one. Just look at it and you'll see. And +1 on removing the bumper. Do it once and you'll say, "wow, that was pretty easy." It's way simpler than the front bumper (I've done that one too).

HenryPcar

I didn't remove the rear bumper on my 997.2 when I changed the sparks plugs. Removing the side mufflers are necessary to gain access to the coil, plugs and the side plates.

snaphappy

Ok I think I get it now, the cat bolts only need to come off because I'm installing the Fister mufflers. Loosen two to get the bracket off and transfer the bracket to the Fister mufflers. Ok glad I got that figure out before I started!!

Bruce In Philly

2009 C2S 140K miles

You do not have to remove those three evil cat bolts to change your plugs or to remove the two side mufflers. The only time you have to remove those three !*#@#$! bolts is to remove the center muffler for a bypass (X) pipe. Also, you do not have to remove your muffler tips to remove your muffler.

When I change my plugs, I remove the bumper, side panels, and the side mufflers... way easier for me. I've done this on my 997.2 and did it on my friend's 996. Works the same. See my post #60 in this thread for access to the two aft muffler bolts. You need to remove the bumper and the side panels to get easy access to these two muffler bolts. You may be able to get at the plugs, or these bolts... whatever... without taking off the bumper but I can't do it. I don't like laying on my back under a car... just won't do it.

Sing the song for my 997.2: The engine block is connected to the exhaust header... the exhaust header is connected to the catalytic converter... the catalytic converter is connected to the center muffler (the X pipe in my case) by three evil bolts... the center muffler/xpipe is connected to the muffler .... the muffler is connected to the exhaust tips. The Muffler is held in place on the chassis by three fasten points: two brackets fore and aft on the muffler and the pipe clamp/collar to the center muffler/xpipe.

Top tip: plan on using a variety of cuss words. I found different words work better on different clamps and bolts... this is personal and I will not give advice on them although you will need them I assure you.

Peace
Bruce in Philly

snaphappy

Everything went really well. Passenger side done. Had one plug that creaked and fought as I removed it. Seemed scary, but it was fine.

BUT. I didn't listen to you guys and removed 2/3 bolts around the cat. And I snapped one off. It was the easiest one too and I got greedy and used a breaker bar - it snapped. So if you picture the three cat bolts in your head, the one I snapped is at 4 o'clock. Here's my question - can I just leave it as is? There is half a bolt rusted in there. So it's probably pretty solid, lol!!!

But overall I want to do the responsible thing - what would you guys do?

PS - I have no idea how to get it out. I beat on it with my punch set... but it's threaded in there right?

swingwing

The shanks are serrated, not threaded. With a correct size punch and heavy hammer you should be able to punch it out. You may have to heat the flange with a torch - smelt and pelt as it were. When you get the offender out, just replace it with a regular bolt and nut. In picture in post #171 you'll see the new copper exhaust nuts I put on the flange bolts. Because of heat cycles, corrosion and rust it's always good to use new fasteners when you can.

snaphappy

I don't have a torch. I'll beat on it and see if it comes out. Or maybe once I drive it I'll beat on it - it will be hot then.

Ok guys, in typical fashion I made a mistake. After I installed the spark plugs I started torquing everything to 22lbs. I didn't break anything. Thank god. But the coils are torqued to 22lbs - is that bad????? Be honest! I just realized they're supposed to be 7.5lbs. All the other bolts that hold on the mufflers, the heat shield, everything is all torqued to 22lbs. Do you guys know the correct amount of torque? Anything I should go back and loosen?

Thanks so much for all the help!!

HenryPcar

No, coils are held by fasteners onto the plastic body of the coils and I can't see how you could torque it down to 22lbs without breaking it.

snaphappy

Somehow I did though. Drivers side is correct at 7.5 lbs. I don't know, I'm thinking about leaving the passenger's side coils at 22lbs unless someone tells me otherwise.

Bruce In Philly

I am surprised they didn't strip the block. If you did, no big deal. In the "old days" wires were just pushed on. Don't worry about it. IMO

Peace
Bruce in Philly