Lowering boost pressure.

[Rumpig]

Sounds like you have a boost leak in that case. Check all your intercooler piping especially the silicon joiners for leaks

Or an exhaust leak, maybe cracked egr pipe.
I fitted my own snorkel and at the time thought i probably could have done a better job. Ended up pulling it off much later for another look and found i had to remove a heap of overlap where it joined together inside the guard. Was much quieter afterwards.

 

[Wortho91]

This isn't the first diesel car I've owned everyone neither am I inexperienced in this field. Diesel engines are all I work on. If I thought it couldn't be changed I wouldn't be on this forum. So please if you have a genuine opinion or information to share I'd appreciate it if it is a smart comment please keep to yourself.

 

[bods]

Or an exhaust leak, maybe cracked egr pipe.
I fitted my own snorkel and at the time thought i probably could have done a better job. Ended up pulling it off much later for another look and found i had to remove a heap of overlap where it joined together inside the guard. Was much quieter afterwards.

Seems coincidental that it was only after fitting the intercooler. ...

On another note, is that the factory snorkel or an aftermarket one?

 

[Wortho91]

It's a factory snorkel. I'll have a look in the snorkel sometime could be an answer there. Don't think it's a leak it comes on mainly going up hills towing there will be a minor noise at around 3200 then it'll get gradually louder as you get closer to 2800 where it peaks. This all happens worst 4th full throttle. It only started with the intercooler.

 

[bods]

It's a factory snorkel. I'll have a look in the snorkel sometime could be an answer there. Don't think it's a leak it comes on mainly going up hills towing there will be a minor noise at around 3200 then it'll get gradually louder as you get closer to 2800 where it peaks. This all happens worst 4th full throttle. It only started with the intercooler.

That's when the turbo will be working at its hardest. Even if you have a small leak that's when it will show itself. Does the piping that comes in the kit have a lip on the hard piping or is it just flat pipe?

 

[Wortho91]

All the piping has the lips to clamp to. TBH I was thinking more along the lines of a manufacturing fault in the cooler. I'll just take it to work one afternoon and pump 20psi up it. Hopefully come across something.

 

[bods]

Yeah that'd work too. Could be a dodgy weld or pinhole in the core somewhere... I guess to eliminate it you could always remove the cooler and put a piece of pipe in there to eliminate the cooler itself ..

 

[tweak'e]

. The next noisy part is the intercooler. Works great with keeping the egts under control but the noise is ridiculous. It sounds like running your finger over a wine glass only high pitched and 10 times as loud.

did you pressure test it after install ? really handy and it shows up leaks fairly quickly.

i think you probably have a leak somewhere or your hearing turbo noise.
they are fairly noisy especially when your hard on the gas towing. changes in intake can change turbo sound.
also check around exhaust and egr pipe for any leaks.
is the intercooler piping rubbing against something?

i hate to say it but if you want it quiet for cruise (probably won't change things when towing) is to unblock the egr pipe (and enable swirl valve). butterfly mod could stay.
you should see boost drop a bit at cruise which should also lower noise.

 

[Jased22]

Did you remove pre cleaner and install forefronts bypass pipe?? They make alot of noise. I think it sounds awesome though!!

 

[Forefront Industries]

the intercooler itself wont make any noise difference....an increase of induction noise can come from installing the prefilter removal pipe that is part of installing the intercooler kit.

would be good if you could get a video of the noise

as members on here know there is sooooooooo many things that cause a high pitched whistle on a zd30 d22....but it would be interesting to hear it first....might give us some clues.

 

[Wortho91]

It had the bypass pipe in for over 20k. The noise came with the intercooler kit.

 

[Wortho91]

Really need some weight behind it to make it loud. It was alot louder up hills towing a caravan on our last trip. Most of the video is full throttle holding it back with the brakes. http://youtu.be/bFU5hwe4HkU