General Knocking sound after driving thru standing water

[tonyn]

Has anybody come across this before or can offer any advice please?
2004 1.2 Panda.
A load knocking sound after driving thru water comes from the passenger front corner and it then stops after a minute or so.
Baffled by it.
Havent been underneath as yet to look at anything
Was hoping someone would be able to point me towards a solution.
Thanks in advance

 

[A3jeroen]

Water in a CV joint?

gr J

 

[varesecrazy]

Has anybody come across this before or can offer any advice

A load knocking sound after driving thru water comes from the passenger front corner and it then stops after a minute or so

Thanks in advance

LOUD noise..

How repeatable..?

Every drive.. hot or cold..??

Could be drivetrain.. could be displaced plastic shrouds.

 

[portland_bill]

There was a similar thread recently, with a suggestion that it was the exhaust reacting to the sudden cooling.
Recently I've experienced this after puddles, yet to crawl underneath and prod at stuff.

 

[portland_bill]

There was a similar thread recently, with a suggestion that it was the exhaust reacting to the sudden cooling.
Recently I've experienced this after puddles, yet to crawl underneath and prod at stuff.

Crawled underneath today. Centre exhaust mounting rubber is trying to fall apart. It has a fabric strap around it, presumably to contain it when the rubber falls apart, but will not do the job of cushioning the movement. It also hides the deterioration well.

New rubber ordered, I'm guessing it will all be quiet once replaced.

 

[DaveMcT]

The rubber hangers provide noise isolation with the fabric strap wrapped around taking the exhaust weight.

 

[callisr]

There was a similar thread recently, with a suggestion that it was the exhaust reacting to the sudden cooling.
Recently I've experienced this after puddles, yet to crawl underneath and prod at stuff.

It was probably my thread as I experience the same thing. It baffled me for ages but is appears to be thermal shock when water hits the exhaust. When I get a combination of time , decent weather and bothered, I’m going to wrap the exhaust and see how that goes........

Rich

 

[callisr]

This should be the link to my thread, which contains a link to a further thread on the subject....

https://www.fiatforum.com/500/478077-knocking-noise-after-puddles.html

HTH

Rich

 

[DaveMcT]

The bottom of the catalyst has a bracket attached to the engine. However the bracket cracks where it's welded to the pipe or the clamp rots away. You can make a new bracket with some 3mm x 25mm steel and a U-bolt clamp. This supports the catalyst avoiding it's outer case getting cracked and may well reduce rattle down the whole system.

Rattles on the 1.1-1.2 exhaust will usually be from the back end where the silencer box can get closer to the body or axle. But check along the length and make sure the mounting points can't bump anything.

 

[callisr]

I will check that on mine as tomorrow looks like the planets will align to give me some tinker time....

 

[benj111]

Just to echo everyone else sentiments, I've had similar knocking, I also get it in certain high torque situations, I've gone through all the culprits but the noise just isn't coming from the engine bay or wheels, and it isn't repeatable at all. So I've put it down to the middle exhaust mount being missing entirely.

 

[varesecrazy]

Crawled underneath today. Centre exhaust mounting rubber ..

New rubber ordered, I'm guessing it will all be quiet once replaced.

Done enough miles to gauge an improvement..?

 

[portland_bill]

Done enough miles to gauge an improvement..?

Skimmed a few puddles on Sunday morning, no noises resulted. Have also replaced the dogbone. Engine movement seemed a little more than ideal during gearchanges. Old mounting appears to be in good condition, but replaced anyway, engine definitely smoother, as are gearchanges. So whilst not visibly deterirated, age had weakend it.

Not found any puddles since, but all seems well so far. Not really looking to deliberately splash through puddles, as throwing water at the underside is not generally a good idea.