exhaust rattles / vibrations

BahnStormer · June 12, 2020, 08:24

Does anybody have a checklist for exhaust vibrations / rattles?

I know I had this previously where the driver's side exhaust tip (TTE) was angled a little high (I think it was), so the vertical part of that pipe was pushing against the rear sway bar and vibrating like crazy on deceleration...

I'm getting a similar sound now (decelerating ~2000rpm), but the sound is a little lighter, more tinny.... I'll have a look this lunch time, but though I'd ask the forum for the list.

BTW - I've got the Toyosport manifold + TTE, so this won't be a completely OEM question, but I'm sure there's a list of usual suspects?

Nvy · June 12, 2020, 09:03

My TTE had one of the inner pipes broken off, it was a solid metal to metal sound when coming off a speed bump or when stepping hard on the brakes. Not related I guess but just wanted to add it.

Carolyn · June 12, 2020, 11:09

Could have a crack in the manifold.

BahnStormer · June 12, 2020, 11:58

Quote from: Carolyn on June 12, 2020, 11:09Could have a crack in the manifold.

please don't say that.... brand new ToyoSport!

Carolyn · June 12, 2020, 12:03

Ok, I won't say that!

did you use OEM crush rings? The composite gasket is Ok at the cylinder head, but I'm not too keen on them at the cat.

BahnStormer · June 12, 2020, 12:52

Pat Chambers fitted them, but yes: OEM crush rings and gasket.

I'll have a bit more of a poke around there later but I feel like I'm looking for a loose metal plate of some sort - the main candidate was the catalytic converter shroud as that looks pretty ropey, but there's nothing that feels loose when the engine is off and I give it a decent amount of pushing and pulling...

It's NOT a constant rattle - similar to when the exhaust tip was too low and fouling on the sway bar, except that was for a few hundred rpm and a heavier shudder... this is a much more lightweight metalic rattle only on deceleration down from 2100rpm-2000rpm...

The only metal on metal contact I can see has been on the driver's stide, between the TOP part of the exhaust hangar and the subframe... I'm not sure it is still happening though - it looks like there is ~5mm clearance now, but I guess that would catch with a little vibration the same as before... and it would only be a light tough, so a light tinny rattle... I'll try wedging a scrap of exhaust hangar rubber in the gap as a temporary test - the vibration is pretty easy to reproduce now, so I'll know if it works...

Joesson · June 12, 2020, 13:28

Déjà vu! Not so long ago an unusual rattle was a frequent comment, generally found to be to do with the main cat. shrouding and was cured in many ways, from stuffing the shroud with wire wool to fixing exhaust clamps in close proximity to the 3 amigos.

BahnStormer · June 29, 2020, 18:22

Quote from: Joesson on June 12, 2020, 13:28Déjà vu! Not so long ago an unusual rattle was a frequent comment, generally found to be to do with the main cat. shrouding and was cured in many ways, from stuffing the shroud with wire wool to fixing exhaust clamps in close proximity to the 3 amigos.

I'm not going to celebrate just yet, but this seems to have done the trick for now: two of the bolts were sheared, so it was rattling a fair bit... two metal cable ties for now and I'll look at something more industrial if it stays rattle-free until those snap....

Joesson · June 29, 2020, 18:44

@BahnStormer
Finding the problem is halfway to fixing it.
Your Cat shields look to be in a similar condition to mine when they were rattling.
I removed them completely and refitted with stainless nuts and bolts and a couple of U shaped exhaust clamps at the flex end.
While the heat shields were off I wire brushed them with a power tool. They came up shiny !

BahnStormer · July 2, 2020, 08:11

Quote from: Joesson on June 29, 2020, 18:44@BahnStormer
Finding the problem is halfway to fixing it.
Your Cat shields look to be in a similar condition to mine when they were rattling.
I removed them completely and refitted with stainless nuts and bolts and a couple of U shaped exhaust clamps at the flex end.
While the heat shields were off I wire brushed them with a power tool. They came up shiny !

Nah - mine's good for another 100k

Seriously though - thanks for the advice - I'll definitely look at that as an option if I can get under the car to work on it properly...

BahnStormer · July 25, 2020, 11:26

Quote from: BahnStormer on June 29, 2020, 18:22
Quote from: Joesson on June 12, 2020, 13:28Déjà vu! Not so long ago an unusual rattle was a frequent comment, generally found to be to do with the main cat. shrouding and was cured in many ways, from stuffing the shroud with wire wool to fixing exhaust clamps in close proximity to the 3 amigos.

I'm not going to celebrate just yet, but this seems to have done the trick for now: two of the bolts were sheared, so it was rattling a fair bit... two metal cable ties for now and I'll look at something more industrial if it stays rattle-free until those snap....

Does anybody know what size jubilee clips this would need to tighten it all up a bit? I'm just concerned that those stainless zip-ties aren't going to last forever!