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Metallic rattle when pulling away under load – i20 N

aimargg42

New Member
Aug 16, 2026
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0
1
Beasain
Hi everyone,
I'm trying to track down a metallic rattle on my i20 N and I'm hoping someone here may have experienced something similar.

The noise mainly occurs when pulling away in 1st gear at low RPM, when the engine is under load.

It can also appear at low RPM in other gears, but it is most noticeable when setting off.

Interestingly, I cannot reproduce the noise while revving the engine in neutral, so it seems to require the engine to be under load.

The noise is noticeably more pronounced in N mode, while it is much less noticeable in ECO.
Once the RPM rises, the rattle disappears. It generally seems to occur around the same low-RPM range each time.

It sounds like a metallic vibration/rattle, rather than a deep knock. The car drives perfectly normally otherwise, with no warning lights, loss of power or any other symptoms.
So far I've checked a few things:

I temporarily disconnected the ESG, but the rattle remained.

I have now physically removed the ESG completely to rule out the module or its mounting as a possible source.

The turbo heatshield has some movement/play and can make a metallic noise when moved by hand. However, after reading other posts, I understand that some movement may be intentional to allow for thermal expansion, so I haven't modified it yet.

I also checked the plastic trim around the accelerator pedal, as I found a similar case mentioned on the forum, but mine is very firmly secured and doesn't appear to have any play.

I removed the scuttle/cowl panel and found that some of the original felt material on the contact/support points was hard, cracked and deteriorated. I removed the old material and installed 1 mm flexible foam tape on the three contact points between the cowl and the windshield to isolate and dampen any possible vibration.

Everything was refitted correctly and all clips/fixing points seated normally.

After doing this, the rattle is still present, but noticeably quieter. The apparent source still seems to be around the front of the car / engine bay, rather than inside the cabin.
The noise still occurs at roughly the same RPM range and under the same load conditions.

I'm currently wondering whether it could be related to an exhaust heatshield, turbo heatshield, exhaust bracket/clamp, engine movement or another component that resonates only when the engine is under load.

Has anyone experienced this exact behaviour on an i20 N — metallic rattle at low RPM when pulling away under load, which cannot be reproduced while stationary in neutral?
Any ideas or experiences would be greatly appreciated!

Thanks!
 
Unless you're running a tune, it sounds like engine knock due to low octane fuel. The shaking can cause vibrations in any number of areas including the heat shield.
 
Unless you're running a tune, it sounds like engine knock due to low octane fuel. The shaking can cause vibrations in any number of areas including the heat shield.
I'm running 95 RON, which is the recommended fuel. My friend also owns an i20 N and runs 95 RON as well, with absolutely no rattling or knocking noises.

My car also feels completely normal otherwise — no hesitation, misfires, loss of power or warning lights. The noise is very clearly metallic and seems to come from the engine bay.

I've also found that my turbo heatshield has some play and produces a metallic rattle when moved by hand. However, after looking through several other posts, I've seen that some amount of movement/play in this heatshield appears to be normal and is apparently necessary to allow for thermal expansion. So I'm not assuming the play itself is the problem; I'm investigating whether it could be resonating or making contact with another component under load.

I'll try 98 RON at some point just to completely rule out fuel-related knock, but at the moment I don't think fuel quality fully explains the physical rattle I'm hearing.