Transit mk7 2.2 euro 4 strange resonance

[Jm7812]

Hi folks,

My vans started making a strange noise, it sounds like a droning at 1500rpm then disappears and reappears at just under 3000rpm sounding like air blowing over a bottle. Noise disappears sharply at 3000 rpm.

Had a new turbo which made no difference
Smoke pressure tested intake and found no leaks.

Has a hole in exhaust flexi but it’s been like it for years and only just started making the noise
Doesn’t make the noise at idle but does have some slight blowing/grrr sound at those specific rpm

Any ideas?

https://youtube.com/shorts/bfpjRISj0nM? ... 4TlkHJNky1

Thanks

[metalworker0]

video hopeless you don't hold it there for long enough ..

so i guess no one can answer with so little input

all the best.mark

[Jm7812]

Thanks for having a listen.

Longer video it’s making the noise throughout however loudest as I approach 3k rpm
https://youtube.com/shorts/qnspm4ZekfQ? ... h7V4SwUWlY

[Jm7812]

video hopeless you don't hold it there for long enough ..

so i guess no one can answer with so little input

all the best.mark

Thanks for listening it’s hard to keep it making the sound as slight throttle position change makes it go https://youtube.com/shorts/qnspm4ZekfQ? ... h7V4SwUWlY

[metalworker0]

That's a hard one, that could be lots of things!
for me it means typing a huge list of things to check, when i know that someone here has had that happen and will point you to exactly what it is ..
If no one comes here by this time tomorrow and tells you what it is
Then i'll make the list out of what to check and how to check..

btw .. the most simple thing it can be, is a loose heat shield

all the best..mark

[Jm7812]

That's a hard one, that could be lots of things!
for me it means typing a huge list of things to check, when i know that someone here has had that happen and will point you to exactly what it is ..
If no one comes here by this time tomorrow and tells you what it is
Then i'll make the list out of what to check and how to check..

btw .. the most simple thing it can be, is a loose heat shield

all the best..mark

Sounds promising, thanks. Just about had enough of it now!

[Jm7812]

Some extra info - the noise can only be heard inside the cab! Sounds normal from outside

[metalworker0]

That statements only made it worse for me to diagnose

NOW i got to ask is it the speed its hitting or the RPM

Yes i know you show .. so much rpm and the sound happens .. but that could also equate to a certain speed, cause if so we'll be looking at air vents . windows, gear linkages, driveshaft , engine mounts , engine vibration damper=the crank pulley.

i say ..

one thing at a time

You have a look at the heat shields .. and report back

this could go on for a long time .. unless someone comes here .. having heard the same thing and knows its cure

all the best mark

[Jm7812]

That statements only made it worse for me to diagnose

NOW i got to ask is it the speed its hitting or the RPM

Yes i know you show .. so much rpm and the sound happens .. but that could also equate to a certain speed, cause if so we'll be looking at air vents . windows, gear linkages, driveshaft , engine mounts , engine vibration damper=the crank pulley.

i say ..

one thing at a time

You have a look at the heat shields .. and report back

this could go on for a long time .. unless someone comes here .. having heard the same thing and knows its cure

all the best mark

RPM related not speed.

It’s not heat shield, I put some self tappers in to tighten it and there was no difference sadly

Thanks again for trying to help