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I'd bet on a boost leak somewhere myself.

The 'ping' could have been a clip or clamp failing, or maybe - unlikely - there is a hole in the inter-cooler like from a stone or something which was just coincidental with the redlining.

Edited by Tony de Wonderful
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I would check all your ic piping first, though when i've experienced vacuum leak the turbo absolutely screams and the car wont run at anything more that 10% throttle, leaving masses of petrol in the wake behind the car, though i guess it could be more of a split in a hose which could be from a smaller hose. Try opening the bonnet and getting someone to rev a bit while youre searching for any weird noises, the 'tink' noise sounds more like something solid hitting something solid though....could 'some' of the fins have shattered? leaving enough to boost 4 psi? you could drop the dump pipe and intake off the turbo and have a squiz to eliminate the turbo too.

btw, why flame the guy for giving advice? we're all entitled to try to help, regardless if its the correct diagnosis or not, if he was a ****head or something i would probably understand why you're being so critical. He stated he was new to these engines, and therefore probably these forums, so why not try and make him feel welcome, not try to make him look uneducated and alienate him?

Any clown can guess a number of ridiculous things, as you have.

It would be good to go off something a good mechanic says may have caused the issue.

Save your diagnosis for wasteland please.

What a ridiculous thing to say. Why not help the guy understand why it couldnt be a bent butterfly? We're a community, with different ideas and views, but every time i come to the forums i have to consider the fact someone like you is probably going to try to flame me for no reason.

That said, you're probably right, and its not a bent butterfly, but come-on he was trying to help and you diddnt have rebuke, it wasnt a personal attack on you.

could 'some' of the fins have shattered? leaving enough to boost 4 psi? you could drop the dump pipe and intake off the turbo and have a squiz to eliminate the turbo too.

Would that not either make vibrations, or quickly crater the turbo totally 'cos it would be out of balance and the forces are very high at the speed the turbo spins?

Boost leak x3 ish

Look for split hoses etc

Go figure.

It is a shame it degraded but Phil has been around the block a few times with his car and a few of us have experienced these issues and seen these threads a number of times with the result nearly always being aging brittle hoses or old hose clamps.

Funnily enough, as of last night I'm also having boost issues.

Induction doesn't sound much different, and no other loud hissing sounds, but I'm not making more than ~7psi. Even with the hose to the actuator disconnected, it doesn't want to boost... :devil:

Time to rip apart all my piping etc.

Would that not either make vibrations, or quickly crater the turbo totally 'cos it would be out of balance and the forces are very high at the speed the turbo spins?

probably, just strange how symptoms of what seems to be the same issue can be completely different car to car.

Go figure.

It is a shame it degraded but Phil has been around the block a few times with his car and a few of us have experienced these issues and seen these threads a number of times with the result nearly always being aging brittle hoses or old hose clamps.

:banana:

Tell me about it, the amount of times i've blown MAP sensor lines, fuel pressure regulator lines, wastegate lines...well you get the picture. I have lost count.

The fact is in most cases the problem is the simplest of all the choices. I have spent hours trying to fix things not understanding why they wouldn't work and then find simply a loose earth or a disconnected plug or something similar.

When people (and funnily enough it always seems to be mechanics.....go figure) start going on wild goose chases blaming this and that it is always the simplest thing never the most complicated.

That's what I have found anyway.

Glad you sorted it.

:banana:

Tell me about it, the amount of times i've blown MAP sensor lines, fuel pressure regulator lines, wastegate lines...well you get the picture. I have lost count.

The fact is in most cases the problem is the simplest of all the choices. I have spent hours trying to fix things not understanding why they wouldn't work and then find simply a loose earth or a disconnected plug or something similar.

When people (and funnily enough it always seems to be mechanics.....go figure) start going on wild goose chases blaming this and that it is always the simplest thing never the most complicated.

That's what I have found anyway.

Glad you sorted it.

hahah yeah Ive done the same...and had random mechanics tell me that it's a bent "push rod" .....on a Rb25 lol

Also, running no BOV could potentially weaken the (nylon) compressor wheel of the stock turbo

no it doesn't.

well you cant say running no bov does you any benefit as opposed to runnning a bov its there for a reason and as you said some people are lucky its does cause a unbelievable amount of stress when your compressor wheel chops up the air

best regards chris

no it doesn't, the VL turbos and HR31/C31 skylines and cefiros came from the factory without a blow off valve, it is a complete non issue, the F1 turbo cars ran something like 50psi with no BOV without issue, there are hundreds of cars running far more than standard levels of boost without causing any issues not to mention all the rally cars that run no BOV as well.

sounds like a popped off intercooler pipe, makes a ting noise and you can make about 2psi before it stalls from getting too rich

Edited by Rolls
no it doesn't.

no it doesn't, the VL turbos and HR31/C31 skylines and cefiros came from the factory without a blow off valve, it is a complete non issue, the F1 turbo cars ran something like 50psi with no BOV without issue, there are hundreds of cars running far more than standard levels of boost without causing any issues not to mention all the rally cars that run no BOV as well.

sounds like a popped off intercooler pipe, makes a ting noise and you can make about 2psi before it stalls from getting too rich

You're getting annoying.

Tell me, in as much detail as you can (with references), WHY Nissan among other companies installed a BOV from factory on cars. If there is no need whatsoever in releasing the pressure in the intake when the TB is closed, then why did they bother? If it's not going to do any potential damage or cause undue stress on components, are you saying that the engineers designing this shit are retarded? Perhaps once you're done justifying this once more for me (us), you should get onto contacting them (among other companies like Borg Warner who have gone as far as to integrate the recirc valve into their turbos) and tell them you think what they're doing has 0 benefit.

fark.

Lighten up a little.

Nissan like any other car manufacturer has variations throughout their models, brain snaps if you will.

Ca18det, no BOV yet SR20det has BOV

Never seen a BOV on an auto Rb20 or 25 yet the manuals come factory fitted.

Big company, lots of different ideas. Some good, many ratshit.

Lighten up a little.

Nissan like any other car manufacturer has variations throughout their models, brain snaps if you will.

Ca18det, no BOV yet SR20det has BOV

Never seen a BOV on an auto Rb20 or 25 yet the manuals come factory fitted.

Big company, lots of different ideas. Some good, many ratshit.

It's only annoying because this certainly isn't the first time he's said a BOV is pointless (or words to that effect)

Automatics wouldn't have it due to the TB not closing between gear changes...but throttle off when slowing down would still warrant one I would have thought...ah well.

I'm not saying that NOT running a BOV will definitely cause damage to the turbo, hands down...what I am saying, is that surely it will cause extra stress, potentially causing damage. It's fitted for a reason - to relieve pressure when the throttle is closed. Removing it might not have any adverse effects.

People have also pushed 20psi through a stock RB25 for years without issue, yet people running 10psi experience problems. Doing something to the engine that differs from how it came factory is asking for problems.

You're getting annoying.

Tell me, in as much detail as you can (with references), WHY Nissan among other companies installed a BOV from factory on cars. If there is no need whatsoever in releasing the pressure in the intake when the TB is closed, then why did they bother? If it's not going to do any potential damage or cause undue stress on components, are you saying that the engineers designing this shit are retarded? Perhaps once you're done justifying this once more for me (us), you should get onto contacting them (among other companies like Borg Warner who have gone as far as to integrate the recirc valve into their turbos) and tell them you think what they're doing has 0 benefit.

fark.

It doesn't have zero benefit, it has very real benefits and I have explained them in the past. The benefits are it doesn't mess with the AFM signal causing it to reverberate up and down when you use partial throttle or completely back off causing flutter, this in turn makes it easier to tune and avoids the car running very rich when it flutters, it also stops the ridiculous tutututt noise which makes customer go wtf is up with my car, turbo life is not proven to be one of these reasons and has never been specified by them to be one of these reasons.

Also a recirc bov allows the turbo to be bypassed at idle and low rpm causing better response and fuel economy. You don't bend bloody blades via the air though, if this was the case you'd bend the throttle plate every time you shut it!

Search for my prior posts, I've said the same thing for the last 3 years, the flutter thread has about 20 pages of arguments showing that bovs aren't to stop turbos grenading, I will find it for you.

Read this, everyone came to the same conclusion as me

http://www.skylinesaustralia.com/forums/FL...BOV-t60655.html

I never said you shouldn't use a bov or a bov is pointless, just that not using it won't kill your turbo, hell I run one myself (modified).

Edited by Rolls

I'm sure that on a steel wheeled turbo the blades wouldn't take much stress at all, but for a stock 15+ year old nylon wheeled turbo it might just be enough to snap fins.

Edited by Trozzle
I'm sure that on a steel wheeled turbo the blades wouldn't take much stress at all, but for a stock nylon wheeled turbo it might just be enough to snap fins.

This has never been seen as far as I know, if you are going to suggest it is possible then you need to do the calculations to prove it, someone in the other thread worked out how much that air effectively weighed and its speed, even if the blades were made of plastic or glass they wouldn't bend or snap, they are attached to a bloody bearing, they can slow down speed up do whatever very easily, if the rush of air going back through them destroyed them then they would shit them selves from normal operation very fast. Even if they were effectively jammed shut (seized bearing) they wouldn't break.

Someone on here had a seized turbo and drove it for a week, the rear blades partially melted and it shit itself, but they didn't break off.

Edited by Rolls

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