horrible exhaust sound at start up (then goes away)

[yesyeah]

Last week I had the check engine light on. Figuring it was my wife not closing the gas cap tight enough, I unhooked the negative battery terminal, tightened up the cap and put the battery back on. No more issue.

 

I also posted here about the squeal at start up (generally only the first start up of the day). The timing belt was put on last year - thinking that or one of the drive betls is a bit loose.

 

Since this is her car, i don't drive it much. However, today, at around 5pm, started up the car and it sounded terrible - i mean, like it had no muffler (we didn't hear that earlier in the day when we first head out). It sounded VERY rough. We drove for a while and eventually that rough sound went away and it then sounded normal. We stopped for dinner and at start up - it did it again, and then it again went away as we drove (about 5 minutes or so into the drive). Then later, moving it from the garage to the street, at start up, crazy rough sound.

 

Does anyone have any idea why this would be? What would make it sound like that and then be fine after a while? I am not sure if it has anything to do with the check engine light that was on (not on now), or her oil leak (rear seal and/or oil pan gasket leak). I checked the oil of course and while it was low, it wasn't bone dry. Needed like a 1/2 - 3/4 quart to make it right.

 

Anyone have any ideas? Please help.

Thanks

 

1999 Subaru Legacy wagon @ 78k miles

[CNY_Dave]

This can be the converter-pipe donut starting to let go.

 

System heats up, things expand, small leak seals up.

 

 

Dave

[yesyeah]

Thanks so much. Any other ideas?

My wife said it didn't really go away at all this time on her morning drive.

 

If it is that converter pipe donut, is that a fix that most shops can handle? It's hard to get to the subaru place, but there is a shop across from her work - was wondering if this was a job in which we could "trust" them.

[sube101]

yes any shop should be able to handle a simple exhaust leek, especially if its just he gasket going out. their really easy to do. takes about 10 minutes

[yesyeah]

was told it was the cat converter assembly. I posted another thread and am trying to delete it but not sure how to get rid of it

 

Sounded like about $600 for the cat assembly and gaskets and installation.

[Olnick]

Could it be that that shop is really into selling cats? I dunno, but it might be wise to go get a 2nd or even 3rd opinion.

[adema2626]

It could be the cat as said, but they make decent money on selling those. If you are thinking about deleting it. Just take off the heat shield covers and take a nice big hammer and hit it a few times and it should break it up and you should be able to dump out the contents Or you could just cut it out and weld in a straight pipe.

 

Oh and almost 99.9% of shops will not take out a cat for you and put in a piece of pipe because that is "illegal", so you will have to find some one that has a welder and do it your self or your friend.

[yesyeah]

Thanks guys - yes, getting a 2nd opinion.

This was the first time where I saw the part HIGHLY exceed the labor in a major way. And when I called back to question it, he said he's make sure yadda yadda yadda. Somehow, the total cost got cut by $150 when he called me back. So we'll see. Sadly, it seems the 80k cat converter federal law warrantly won't help me since the car is older than 8 years - unfortunate.

 

I assume it's okay to drive like this for a while? It sounds horrible though

[CNY_Dave]

If they want to put on a cat because the bolt flange is rusted, there is a slip-on repair flange that works just as well.

 

Dave

[johnceggleston]

+1 what he said, this is not an uncommon problem for a subaru at this age. the repair is what you want, either the flange or the welding. the cats apparently are working fine.