What Did I Break?

[Count Grantleyish]

Hi all,

I have 33 GTR.

It have the following performance modifications;

- HKS Pod filter.

- HKS front pipe (3" to cat).

- 3" Gutted cat.

- HKS 3.5" cat-back exhaust.

- Boost restrictor removed.

Last night, my friend and I noticed something strange. 4,000rpm, it make whistling sound and when it's warmed, it is struggling to build boost. I left it to cool down for couple of hours then drove home, I have no issues building boost to 14psi, after 20 minutes it was struggling to make 1-3psi.

Tried this morning, it did the same then turned the car off for 5-10 minutes, got boost but didn't drive further to really check it again.

No white/blue smoke coming out of exhaust.

I still have oil pressure, and it is behaving like it should.

Checked all the clamps, but after doing some researching it appears the vaccum hoses may be the culprit?

I think the rubber hoses (afm to turbo or FMIC piping) may shrink from the sucking air from the turbos - which may be the case seeing the GTR is 14 years old?

I'm not sure if the air is leaking - I'll need someone to try to hear it for me (I'm deaf so can't hear zip).

Haven't checked the exhaust yet, but someone mentioned exhaust manifold gasket so will check it out.

Any ideas or suggestions?

Godamn GTR!

Thanks in advance.

Grant

[Count Grantleyish]

Anyone know the cause or you're as stumped as I am?

[vic stagea mick]

Anyone know the cause or you're as stumped as I am?

i think your car just gets the shits every time you take it for a sau cruise because it knows your going to give it a hard time and decides to break something guess who is off to see trent again

[Count Grantleyish]

i think your car just gets the shits every time you take it for a sau cruise because it knows your going to give it a hard time and decides to break something guess who is off to see trent again

I think you're into something there...

On the bright side, I didn't need tow truck this time, pretty rapt about that to be honest.

[Count Grantleyish]

Hi all,

Just had someone PM'd me saying the hose or clamps has split so anyone with 33R have hoses in good nick to sell to me so I can test it?

I have someone coming by to have a listen for me later this arvo just to be safe.

Cheers

Grant

[Red R Racing]

Hi all,

Just had someone PM'd me saying the hose or clamps has split so anyone with 33R have hoses in good nick to sell to me so I can test it?

I have someone coming by to have a listen for me later this arvo just to be safe.

Cheers

Grant

[W0rp3D]

Hi all,

Just had someone PM'd me saying the hose or clamps has split so anyone with 33R have hoses in good nick to sell to me so I can test it?

I have someone coming by to have a listen for me later this arvo just to be safe.

Cheers

Grant

That would be my guess, when i split a hose it would still slowly build boost till about 12psi then it would start misfiring and spitting out black smoke, was about 100k's from home so i tried wrapping it in duct tape, didnt work all that well but was enough to get me home.

[Count Grantleyish]

Hi all,

John (ssxRicho) dropped by to have a listen, he said he heard loud screeching but all piping and clamps look to be fine.

We went for a drive and see if it is happening, it didn't struggle to build boost.

Only difference between yesterday and today, yesterday I drove roughly 600km and today, about 30km if any (not continuing though).

Could it be a sign of turbos is on way out even though it is driving just fine, no white or blue smoke coming out of exhaust.

So I'm puzzled once again, stupid GTR. So off to see mechanic for another opinion.

Cheers

Grant

[W0rp3D]

My gtst had a screeching noise which i thought was the turbo, havnt taken anything apart yet but i have notice a couple of exhaust manifold studs are missing, check those first.

[Count Grantleyish]

My gtst had a screeching noise which i thought was the turbo, havnt taken anything apart yet but i have notice a couple of exhaust manifold studs are missing, check those first.

To do that, I'd have to literally dismantle the motor. And while I'm at it, I may as well buy new turbos.

I wish I still kept my old GTST.

[W0rp3D]

you cant see the manifold studs with out taking the turbo's off?

Im talking about the ones in the head not the turbo ones, although it could be them as well.

[Count Grantleyish]

you cant see the manifold studs with out taking the turbo's off?

Im talking about the ones in the head not the turbo ones, although it could be them as well.

Yeah, can't really see without removing twin turbo pipe.

Manifold studs that break, are they usually on top side of the manifold or bottom?

[GTScotT]

Being time dependent means it is heat dependent, meaning its an exhaust component before it is an intake component.

If it were a split in your cooler hoses it would occur from word go.

Although, I had this issue happen to me a long time ago on my fwd SR20. After it was driven for a while it would begin shrieking on boost like you wouldnt believe... and it would struggle to boost properly. The cause; turbo to manifold gasket.

I wouldnt go ripping your turbos out without looking for evidence of carbon stain in that area first.

GL

[Count Grantleyish]

Scott,

What is the best way of finding the carbon stain in crowded engine bay as found on 33 GTR?

I think I'll get new clamps and tear the whole front end to replace them, see what happens after that.

Cheers

Grant

[ARTZ]

Yeah, can't really see without removing twin turbo pipe.

Manifold studs that break, are they usually on top side of the manifold or bottom?

did mine today 2 at the rear 1 at the front were cracked...i initially noticed loose nuts and went to tighten the nuts and one just fellout in my hand..3 cracked in the head..as well my turbo bolts were loose...seems to be common problem on gtst not sure about gtr...Im thinking the same maybe its an excuse for a new turbo...Good luck with it..

[Count Grantleyish]

did mine today 2 at the rear 1 at the front were cracked...i initially noticed loose nuts and went to tighten the nuts and one just fellout in my hand..3 cracked in the head..as well my turbo bolts were loose...seems to be common problem on gtst not sure about gtr...Im thinking the same maybe its an excuse for a new turbo...Good luck with it..

Yeah, it is 14 year old so it happens.

It's bit of a bad timing considering I sold my perfectly good pair of HKS 2510s that I was going to put in my GTR, so will need to go turbo shopping...

Like I said earlier, I'll change the clamps and go from there.

[ARTZ]

If u put your hands down around where the bolts are you will feel if they are loose...

[Count Grantleyish]

It's going to be a problem seeing I have a GTR - on a GTST would be easier.

[ARTZ]

If you take the top intake pipe off from the rear turbo it should be accessible...it will be the very end bolts if its the problem all

[Dan_J]

is it a high pitched type girly scream/screech that you only get at high rpm's(5000-6000+)?