1kz violent shutoff (1 Viewer)

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As willy says, just connect all the hoses and see what happens.
Have you ascertained it is getting vacuum?
All hoses look connected. Not sure how to check if it’s getting vacuum since I’m not much of a mechanic, tips? I’ve noticed considerably worse fuel consumption this last tank than usual, got around 12 MPG. Low fuel lights on at around 360KM where I’m usually in the 400s when it comes on. Although I will admit ive gone harder on the truck than usual this tank, went out on some trials but I don’t think it would’ve messed my MPG that much? ( maybe I’m just overthinking hah)
 
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You can usually feel vacuum on the end of your finger if its there. But you would have to get someone to shut it down while you feel it. Or remove the body from the manifold and test it. Have you inspected the vacuum pump?

Just took my kzj78 into the mechanic for the valve cover gasket and also the crossover pipe/ turbo inlet gasket
He was working very close to the shutdown components and it wasn't there before you took it to him.
 
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You can usually feel vacuum on the end of your finger if its there. But you would have to get someone to shut it down while you feel it. Or remove the body from the manifold and test it. Have you inspected the vacuum pump?

He was working very close to the shutdown components and it wasn't there before you took it to him.
You can usually feel vacuum on the end of your finger if its there. But you would have to get someone to shut it down while you feel it. Or remove the body from the manifold and test it. Have you inspected the vacuum pump?

He was working very close to the shutdown components and it wasn't there before you took it to him.
If I’m being honest, I looked at the turbo/ dump pipe right when it shuts off and it shakes a lot. Not sure if that’s normal since I never looked at the turbo while shutting off before the violent shake. I’ll feel around for vacuum leaks.
 
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When checking the vacuum I meant to remove the hose and feel if it has vacuum when its activated by putting your finger over the end.
As for the dump pipe, I would check it when cold, but when engines shake to a stop like yours they often cause huge vibration in other components, particularly anything exhaust related.
This is exactly why they have these butterfly valve shutdowns on some engines.

Is there anyone near you who knows their way around Japanese diesels?
 
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When checking the vacuum I meant to remove the hose and feel if it has vacuum when its activated by putting your finger over the end.
As for the dump pipe, I would check it when cold, but when engines shake to a stop like yours they often cause huge vibration in other components, particularly anything exhaust related.
This is exactly why they have these butterfly valve shutdowns on some engines.

Is there anyone near you who knows their way around Japanese diesels?
Unluckily not that I know of, in South California it’s hard to find any diesel shop personally.
 
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You can usually feel vacuum on the end of your finger if its there. But you would have to get someone to shut it down while you feel it. Or remove the body from the manifold and test it. Have you inspected the vacuum pump?

He was working very close to the shutdown components and it wasn't there before you took it to him.
When checking the vacuum I meant to remove the hose and feel if it has vacuum when its activated by putting your finger over the end.
As for the dump pipe, I would check it when cold, but when engines shake to a stop like yours they often cause huge vibration in other components, particularly anything exhaust related.
This is exactly why they have these butterfly valve shutdowns on some engines.

Is there anyone near you who knows their way around Japanese diesels?
Could I send you a video somewhere of the shutoff? Not sure if they allow videos on the forum. Need some more thoughts, the sounds not good. I looked at the all those vacuum hoses and all the shutoff components and it all seems to move when it’s supposed to.
 
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I know exactly what hard shutdowns look like. You have been asked a few times to state if you have vacuum or not. You cant see it , you can only feel it.
This line here does have vacuum during shutoff. I assume it’s working correctly?: not suction when running but right at shutoff it has vacuum

A0DAA260-8DF6-4DF6-80FC-262D982B8A15.jpeg
 

FJBen

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Thats correct, Vacuum on shutdown.

Do you hear a hissing noise with the violent shutdown?
Does it shutdown quickly or sort of prolonged?

You can get a mighty-vac from the auto parts store for like $50.00 so you can test whether that valve is opening/closing the butterfly.

A video would be great.


12mpg seems low, but I would check another tank to make sure you didn't fill it the same, or wind or some other issue came into play.
 
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Thats correct, Vacuum on shutdown.

Do you hear a hissing noise with the violent shutdown?
Does it shutdown quickly or sort of prolonged?

You can get a mighty-vac from the auto parts store for like $50.00 so you can test whether that valve is opening/closing the butterfly.

A video would be great.


12mpg seems low, but I would check another tank to make sure you didn't fill it the same, or wind or some other issue came into play.
Wish forum would allow videos. From what I hear there’s no hissing. And pretty quickly, the whole engine kind of shakes and makes a clunk kind of noise. Startup/ driving feels normal.
 
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Looks like he had the same problem, thanks for the link. All the lines look connected, but maybe I’ll just try pulling and re installing all the vacuum lines around there...
I just had this same issue after taking my intake off to add an intercooler. Check and make sure your actuator arm that closes the small butterfly moves freely so that it closes all the way and is not being blocked by the filter of the VSV.
 
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Looks like he had the same problem, thanks for the link. All the lines look connected, but maybe I’ll just try pulling and re installing all the vacuum lines around there...
looking at your photo I think you are having the exact same problem based on where I see the vacuum lines for your lower VSV. Loosen the bolt that mounts that VSV to your intake and rotate the VSV so that the filter portion of it is out of the way of the actuator arm.
 
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Looks like he had the same problem, thanks for the link. All the lines look connected, but maybe I’ll just try pulling and re installing all the vacuum lines around there...
In this photo, notice how VSV No.2 is angled downward so that the filter does not interfere with the actuator arm. This i show it needs to be for the butterfly to close fully.

Screen Shot 2021-04-28 at 10.35.54 AM.png
 
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looking at your photo I think you are having the exact same problem based on where I see the vacuum lines for your lower VSV. Loosen the bolt that mounts that VSV to your intake and rotate the VSV so that the filter portion of it is out of the way of the actuator arm.
We have a winner. Problem solved, thank you all! Looks like the problem was the lower vsv (vsv2 I think?) was reinstalled completely flat by the shop, it should’ve been upright. I assume it was simply getting in the way of that actuator? Anyway I simply took it off and but it back on the way it should be in the photo and now it’s smooth. Thanks for all the help guys.
 

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