Heat shield or muffler
 

I've got a rattle as the car is warming up...noticeable at idle, but if the exhaust is still cold and I press the gas, I'll get a heat shield sounding rattle around 1500 rpm's.
What's different is that the sound is coming from the rear and possibly the muffler.
Can anyone tell me if there are heat shields around the muffler area or at the back end of the exhaust? Or is it something internal inside the muffler?

I haven't had time to crawl under the car to look, but I am also not allowed to work on a car in my apartment parking lot unfortunately :(

the 1500 rpm rattle is VERY common on these cars it comes from the resonator you can cut it off and weld a straight pipe there instead

There is a heat shield for the muffler. Mine rattles when I slam the trunk.

dcb

There are rattles, buzzes, and other wierd sounds that come from the muffler area. You almost have to crawl under it to find out just what is making the noise. :o

Really? Which part is the resonator, exactly? I didn't see it on the parts diagrams I have... I'd love to kill that damn rattle.:D

I think the heat shield for the muffler may be this one piece that almost touches the back bumper..I thought I saw this once by just looking under the trunk area, but I'll try to jack up the car tonight and crawl under there to see what this ruckesss is about.

Resonator is under the transmission area of the car I believe and my noise appears to be the rear of the car.

I had a buzzing/rattling noise comming from what I thought was my mufflers heat sheild. I let it go because I was having a new exhaust put on in a few weeks. I had the new exhaust put on and it still made the noise. I finally decided to get under the car and take a look for myself. it just ended up being a few very small rocks that found there way up into the lip that folds up on the mufflers heat sheild. after I removed them it hasn't made the noise since. Might be someone elses problem too. Just thought I'd share.

I checked all welds and shields that I could and couldn't find the problem.
I jacked the rear of the car up and layed under there just after starting the car...The noise sounded like it was coming from inside the muffler.....more apparent when I had my ears by each tail pipe....And I checked the tailpipes and they are not loose....The noise went away after a few minutes as soon as the muffler warmed up.

Tell me, is there something in the muffler that would be loose?
What would be the best thing to do, buy a new muffler or take it to a muffler shop to really diagnose it incase I'm missing something, or what?
What is involved in replacing the muffler? Rewelding to the rear inlet pipe, rewelding the tail pipe pieces on, etc.?

Would a loose baffle fix itself when the muffler warms up? That might be my problem.

I looked at parts on Subaruparts.com and what would be required to replace the muffler? New rear exhaust bearing or those rubber seals?

Also, does magnaflow make a better muffler that would fit in place of the subaru one?

Thanks,
sorry for all the questions.

How do these babies sound without the resonator?

from what I've heard terrible...That's why I want to keep mine.

Exhaust resonator
 

I can almost promise the noise is the center resonator. It works like a pre-muffler. If i remember it has a thin pipe inside it that has alot of holes in it. the pipe breaks off and rattles intermittently. I have it removed from my 94 but it is still in place on my 92. Cutting it out does make a noticble increase in noise, and it changes the pitch, but if you didn't know what the car was supposed to sound like you would never know. The noise comes from INSIDE the system, that is why you hear it coming out of the exhaust outlets. The resonator is made into the center exhaust pipe, and is a breeze to replace for any exhaust shop, just remember to order all new bolts and gaskets.

~Nate
ASE L1 master tech

what's the p/n of the resonator? And what other parts would I need if I were replacing this piece?

Not cheap!

The part number is 44205PA000 and is $275.00 plus shipping from subaruparts.com and $350.00 from your dealer.

Part #2 in the diagram.

http://www.subaruparts.com/subaru.diag/2/i440-A.gif

Easier to get another used resonator and cut the pipes at either end of the resonator and weld it back in. Or get another resonator, such as magnaflow or Aero Turbine and put it in the same place,.
.

Does the magnaflow or Aero Turbine sound any different? or better if anyone knows?