Weird rattle under load at 2000rpm

[Blade]

I have a weird clattery rattle only under load and between 1900rpm and 2100rpm. After that it smoothes out. I thought it was an engine noise but can't find anything and I now suspect the gearbox. Has anyone had a similar problem and help me locate the problem?

[Scoobysrt]

https://www.caddy2k.com/forum/viewtopic.php?t=51086

[Blade]

Hi, thanks for the reply but I don't have permission to view it as I'm new to the forum. Can anyone let me know what the thread link is about?

[LouisAMS]

I have same, first thing to do is dog bone mount, it’s likely torque induced nvh from transmission feeding through the sifter cables

[redfella]

I just might be in the same boat.
I can hear a rasp almost like a exhaust blow when under load at 2000rpm, however I can only hear it in first and second gear.
The odd time in First, I can feel a small pull like a bust of acceleration when moving out of this rev range.

I was thinking it could be a sticky turbo but I mentioned it to a mechanic friend and he said it could be the DMF - so I'm not sure.
Caddy is a 2006 1.9 TDI BLS with 176k and mapped to 140ish supposedly.

Also an newbie so if anyone could kindly summarise the linked post it would be appreciated.

[Scoobysrt]

The linked post is a thread by louisams who made a thread a few days ago saying the exact same thing.
It's not a one stop thread for a final solution but had a few posts of advice of where to go from here.

[Blade]

I just might be in the same boat.
I can hear a rasp almost like a exhaust blow when under load at 2000rpm, however I can only hear it in first and second gear.
The odd time in First, I can feel a small pull like a bust of acceleration when moving out of this rev range.

I was thinking it could be a sticky turbo but I mentioned it to a mechanic friend and he said it could be the DMF - so I'm not sure.
Caddy is a 2006 1.9 TDI BLS with 176k and mapped to 140ish supposedly.

Also an newbie so if anyone could kindly summarise the linked post it would be appreciated.

It does sound exactly the same as my annoying noise. Have you got any further diagnosing it?
I want to look at the egr system and see if there's a leak there that's making the noise but it's so hard to get at! I've got the 2.0 bmm engine.

[Kelman70]

i too have this same annoying noise, thought it was a loose heatshield to start with but nothing loose, mine seems to be worse when either turning sharp right/left, notice it at low speeds when driving through residential streets at 20-30mph

[dan@biali]

The noise being more obvious when turning could also be top mounts, cv joints, arb bushes and other suspension related parts.

[redfella]

@Blade - Any joy diagnosing it mate?
I've not been able to get enough free time to look at my own van.

After reading the linked thread above I don't think its an engine mount - I've no abnormal vibrations or anything like that.
I'm starting to think its gearbox / drivetrain related - but there are levels to it !
I also seem to be able to hear a noise like a heat shield vibrating.

[dan@biali]

It could be the dual mass flywheel as your mechanic mentioned. There's a few youtube clips of what that sounds like to compare to yours. Not sure if the release bearing makes a noise when thats failing as well. Are you still on the original clutch and flywheel? 176k miles on original components that usually average a lifespan of about 80k miles and you've tuned the engine so its dealing with more torque which could have worn those parts close to the end of their serviceable life.

[Blade]

Just to update,
I have changed my dogbone Bush and engine mounts. They were shot but made no diffrence to the rattle. Fixed the radiator mounts because the were blown. No change.
Fitted a new timing belt and camshaft and injector seals. No change to the rattle.
Fitted a new exhaust connector. No change to the rattle.

It's really doing my head in.
I do also seem to have a flat spot around 1800/2000 rpm where the noise is and I feels a bit low on power from realy low. Also fuel consumption is pretty bad. All these things are making me think its to do with the egr, dpf and turbo..
Does anyone have any other ideas?
The next thing I'm going to do is remove the dpf and see if it's been messed with[hollowed out badly, resonating] and inspect the egr and turbo.

I do feel it could potentially be the dmf too but my mechanic didn't seem to think so.

[ogimrki]

Hi did you figure out what was the issue i have the same problem on my golf 4 1.9 tdi vibration between 1800-2000rpm only vibrates under hard acceleration when i drive slowly no vibration and between 2000-5000rpm no vibration

[STP]

Heat shield rattle perhaps? Get a small rubber hammer (must be rubber) and tap lightly all over the engine bay, turbo and exhaust heat shields etc. Engine off of course. The rattle will show itself when you get to tapping the right area.