Extremely loud air intake sound when boosting

[dodgypatrol]

Hi Guys,

I am brand new to Patrols, 4x4 and this forum however i am no stranger to mechanical faults.

I recently purchased a lemon (98 GU ST wagon, RD28) and after 4 weeks of ownership i have had, for the best part, a complete motor rebuild.
I got the car back 24 hours ago and this morning a new issue has surfaced. On my way to work, my car suddenly decided to sound like
it was sucking in the entire contents of the universe when spooling. No noise of very low revs or deceleration. there are no warning lights or loss
of power.

I checked all the piping to and from the turbo/IC/manifold whatever to make sure nothing had popped off as such, but it all looks ok (but i am no mechanic).
I didnt have enough time to fully check the IC and piping for splits or cracks, so i will do this later.

Most of the info i have found so far is quite broad in terms of, it could be anything from a sensor up to busted turbo.

I am running out of ideas and i don't want to have to send it back to the shop straight away as i have just spent a very large sum to try and keep this beast.
I will be having the shop look at it seeing as this has only happened after previous repair, however my previous experience with mechanics is they will find some way
to deny the responsibility of ownership that this has anything to do with their work. I'm not hating on the mechanics but this has happened to me many a time before and
i may be a lone soldier on this one.

Any help is greatly appreciated.

(i tried trauling through the forum first but i didn't really seem to find anything that matched a description like mine)

[mudski]

Does it do this when sitting there and you rev the motor up? Or is it only under load? Remove the hose to the intake side of the turbo and give the impeller a spin. See if it feels good and spins nicely. Also any performance loss since this happened?
Sounds to me you might just have a broken intake hose, hopefully.

[Hodge]

Gday mate. How sure are you it's sucking air noise. Could be a leaking exhaust sound ? Turbo manifold maybe ?

I'd be asking the shop as to what's up.

[dodgypatrol]

Hi guys thanks for the replies.

Hodge: The only reason i say air in is because it's only when i accelerate, so i suppose it could be exhaust too, only my previous dealings with turbo's is that when its exhaust
they sound 'farty' rather than something sucking in a huge amount of air...but, i am not 100% sure.

I haven't had time to fully asses this as it only started on my way to work, sorry for the lack of details.

mudski: The piping was only put back on yesterday and it was not doing this when i picked the car up or i would've turned it straight back around lol
So to aswer your question, i have not personally removed the piping as of yet to test the wheel, but my power still feels the same.
Also, I have not tested whilst on idle yet, i will also do this if i make it home.

thanks again guys.

[threedogs]

do you have a snorkel fitted

[dodgypatrol]

No, no snorkel or any aftermarket goodies. As far as i am aware, this is completely stock.

[mudski]

Get a flash light and look up under where the dump pipe meets the turbo and see if there is any black soot sprayed anywhere. As Hodge said it could be exhaust too. Quite possible they haven't bolted the dump pipe up tight enough and its come lose, or even the studs have snapped off. Hope its not the latter....Check after the dump pipe too where it bolts to the mid section of the exhaust.

[Avo]

when I had a new turbo fitted to my car the idiots never tightened up the bolts that bolt on ther turbo properly.took it back to them and they could not find anything either,,But when I contacted the turbo company they suggested I run it up to them.they had it running on a hoist and found the problem in minutes..loose bolts,very hard to see unless it was on a hoist and running.maybe something simular.was a few years ago now.

[Stropp]

i would say the intercooler is split or the pipework.

[dodgypatrol]

I will hop under and have a look later.
Thanks again.

[dodgypatrol]

Hey guys, just an update...

I just had to drive it home from work and pick up the little one, i drove with windows down, radio off etc... seems to sound more along the lines of an exhaust leak when in the cabin.
Motor is too hot to check now so ill have a good suss in the morning. Hopefully nothing major!

[Hodge]

Do those RD28's have an EGR system? Could also be that. Just a thought.

[mudski]

Do those RD28's have an EGR system? Could also be that. Just a thought.

Yeah mate they do but a lose dump pipe maybe be the culprit.

[dodgypatrol]

Hi Guys,

Think we solved it, i jumped under looking for the loose dump, but everything looked great so did all the intake. Everything was clean and tight. After scratching my head and
maybe a few profanities, i saw this shiny thing bouncing around under the IC. Keep in mind i have never seen an IC with an electrical fan attached to it, let alone on with this many connectors/piping etc.. so my description of what i found is bad haha. There was a little right-angle valve/joiner piece thing floating with a bleed pipe still attached to it. I felt around the IC and eventually found a small hole up the back of it and this piece fitted right in, albeit still a little loose. I plugged it in, started up and gave some revs, no black hole yet. I took the beast for a spin and alas! no massive air sound. Ill have to find the correct way to put this plug/valve in so it doesn't pop out again.

Thanks to everyone on their speedy replies and great suggestions, i really do appreciate it, especially being new to diesel, 4x4 and patrols.
I'll keep updated if this permanently solves the issue.

[Hodge]

Great to hear you've solved it mate and even better the fact that it isn't anything more sinister. Easy loose connection or connection is always the best outcome!

[mudski]

Phew! Good find. Stumped at what this thing is you found though...

[BigRAWesty]

Phew! Good find. Stumped at what this thing is you found though...

X2. Could you post a pic of said culprit??

[dodgypatrol]

@mudski; Yeah i think it's just a vac line? it doesn't seem to do much but runs back to some of of stock looking boost controller/bleeder thing with 3 knobs and heaps of lines coming off it.
I have never seen one of these either.

@westy's; I will post a pic of the thing sometime today.

[dodgypatrol]

X2. Could you post a pic of said culprit??
Here is the culprit. It slides into that hole on the back of the IC fairly easily so i'm assuming a seal of some-sort was destroyed in the process of the r'n'r
I traced it back and i connects to about 5 different pieces that eventually ends up on the turbo's actuator. Now that it's in though car runs fantastic.41944

[threedogs]

IC could do with a tub lol
is that your boost hose that goes to your gauge?

[dodgypatrol]

Car has no factory boost gauge, the line joins up to some others on a rail that eventually meets the actuator.

I am thinking of purchasing a Scan Gauge 2 if i can find out if my diag port is OBD2 compatible, but it's proving hard to get a definite yes or no on that one haha

[P4trol]

Obdii won't work on the 2.8s. Have a look at ecutalk.

I find I have to use a cable tie to keep that hose on the barb. When removing the Intercooler, (at least on mine) it is easier to remove the other end of the hose.
My metal piece is loose, but doesn't come out.

Your Intercooler fins are a bit bent over as mentioned too. Might need a careful straighten.

You may want to reconsider putting a clear picture of your key up on the net too.

[dodgypatrol]

X2. Could you post a pic of said culprit??

Here is the culprit. I assume a seal or whatever kept it in place was broken during the r'n'r? since placing it back in correctly
the car runs fantastic.

41945

[threedogs]

so air is blowing out that hose ??
or "B" motor runs like a dog when hose is out
EDIT Is it part of the crankcase ventilation system ??

[dodgypatrol]

motor runs fine, just less boost i'm assuming cause not as much pick-up. The sound it makes is so loud it sounds like a gerni with no water, but only when spooling.

I think it's air in as i could not feel any output when motor was idle.

[threedogs]

did the above pic make any sense to you??

[dodgypatrol]

sorry, no, not really.

[HiluxMichael]

Hey guys, found this today

41957

Same strange intake noise when accellerating, maybe even louder with the snorkel...

Regards
Mick

[dodgypatrol]

It is ridiculously loud for how small the problem is, isn't it? I could swear i was missing half my intake haha

[HiluxMichael]

It is ridiculously loud for how small the problem is, isn't it? I could swear i was missing half my intake haha

x2 :biggrin: