~2000-3000 rpm rattle on decelleration driving me insane

nath · Postby **nath** » Wed Jan 25, 2006 1:02 pm

I had this problem and it turned out to be the heatsheild around the cat itself. After removing the noise dissapeared.

Don't rule out the dreaded gearbox/diff decceleration whine that makes a regular appearance on early NAs, especially if you can hear it from 50m away.

Is it a grinding rattle?? or a rattle rattle?

Grinding rattle sounds more like a reciprocating 'metal' noise which hints to being like the drivetrain noise described above, while the rattle rattle more like an exhaust. I've had both these noises.

Nath

Postby **Okibi** » Thu Jan 26, 2006 2:38 am

JBT wrote:Check for loose baffles in the rear muffler....

My first thoughts too ... also check all your heat shields.

Doies it make the noise if you park and rev the warm engine?

You could get a mate to rev your warm engine and you could run around and try and find the rattle.

maxwolfie · Postby **maxwolfie** » Thu Jan 26, 2006 7:04 am

I ripped the heat shield around the cat off and its still doing it.....

It doesnt seem to be anywhere as loud at idle, however there is a slight rattle coming from the rear end, though it is hjard to hear what it is..

Bevan · Postby **Bevan** » Wed Feb 08, 2006 2:36 pm

So how did you go Max? (hehehe, sounds like Get Smart).
I found out I actually had TWO rattles. One was loud which drowned out a quiter and still VERY annoying one.

First and major rattle was obvious. The two bolts in the picture below were missing:

The second one i'm pretty sure is coming from under the car around the cat converter. Hopefully it's just a blown gasket like it was last time but I doubt it cause it's not vibrating on throttle, just decelleration. Probably won't get under the car for a week or two though...

maxwolfie · Postby **maxwolfie** » Wed Feb 08, 2006 9:52 pm

Still no luck Bevan

QwikMX5 · Postby **QwikMX5** » Thu Feb 09, 2006 8:56 pm

I know i have heard this somewhere before, maybe on the big forum, but here goes..

"Try jacking the car up and tapping the exhaust with a rubber mallet along the length of the entire exhaust system. Apparently, this creates vibrations similar to when driving, so you should be able to home in on the sound"

Worth a shot? :?:

Bevan · Postby **Bevan** » Fri Feb 10, 2006 9:50 am

Thanks! Will try when i'm under the car

Curly · Postby **Curly** » Sat Feb 11, 2006 2:39 am

nath wrote:Don't rule out the dreaded gearbox/diff decceleration whine that makes a regular appearance on early NAs, especially if you can hear it from 50m away.

Any more info on this noise - my NA seems to have developed it of late...

Is it a precursor to gearbox problems, or caused by using the wrong gearbox oil/diff oil?

Car still shifts sweetly, but sounds a bit substandard - especially when driving next to concrete walls etc.