Ok, my main tick seen in my other thread is not solved. And its worse.

But I wanted to create a solution thread for a different rattle I had just in case someone faces the same thing.

On acceleration I get a detonation/knock pebbles-in-a-can sound. I have been fairly sure its not knock since it occurs all the time hot or cold, moderate to hard acceleration, and the car seems to accelerate fine. Maybe I have screwed up or worn valves but I haven't heard of that in these cars.

So today I went to hunt my main ticking sound down but also to give my detonation rattle sound a shot too. Like I before I banged on the driver's side exhaust with a mallet, except today I banged much much harder. Sure enough the two rear cats, which are nearly touching they sit so close, started rattling together loudly. I crammed some heater hose up in between their close points and the acceleration rattle is gone.

The car sounds much happier.

 

Way to troubleshoot OZ!
Glad you found it.
Any idea if you knocked the material loose in the cat by banging on it? If it is loose you may now have a bunch of crap sitting inside your cats.
Heard where someone (Woody perhaps?) gutted his cat by banging on them.

 

I would suggest that you get a bar to realign the pipes, the heat is terrific and the house will stink and probably burn.

It will take some effort, you could assist yourself by loosenin g the 12 and 13 MM bolts where the pipes to the resonator connect to the rear cats, then shift the pipes and retighten the bolts. Be safe under there, Woody

 

Well, I'm not following... Woody, is your suggestion meant for someone who gutted his cats? I didn't gut my cats, I just knocked on the pipe to identify where my vibration was, then jammed some heater hose up in there to solve the rattle/vibration.

I didn't take my exhaust off or bang the cats inside to gut them.

But if you're saying the cats clanging together is a sign I need my pipes realigned.... ?

 

If the pipes are close, then they need to be aligned to MISS one another, its hard to move the pipes around unless you release the clamping tension. If you loosen up the exhaust bolts, it will be easier to shift the pipes to clear one another. Just a suggestion, to solve it in a more secure fashion. Woody Enjoy.

 

they should not be hitting each other and the exhaust generates so much heat that it will eventually catch that hose on fire. you need to get the pipe aligned or at least bend it some so they do not touch.

 

I'm definitely a "dog" guy, but gutting cats is too extreme. Even for me


It's especially cruel if you gut your cats and then bang them together.

 

WHen you nail it the exhaust really barks more than before, Woody

 

Haha.....

Now were speaking my language.

 

lol...that's great

 

Interesting, thanks guys. Its the weld points, or weld lines, that are hitting. They're just so darn close together. I read of an slk32 guy who reached in there with some sort of filing device and filed away a little on the thick weld lines or whatever they are exactly and that fixed it.

And can heater hose really catch on fire? And do the rear cats really get that hot? Oh goody I can drive around scared about a fire.

 

I have seen OVER 500 degrees on the TAIL pipe outlets, oh yeah like I said, there is the potential for the hose to belt, stink and even burn, Not a big deal except it could burn wiring under there, Watchful Woody.