Cabstar nt400 problem

[dig-dug-dan]

Not sure if any of you guys can help, yesterday when pulling away from a roundabout, loud bang, then my engine sounds like the exhaust has gone, but with a bag of nails thrown in. No engine light present.

Exhaust fine, sounds awful ,and no power up a hill, barely got over 20.

Truck recovered on a low loader and is sat at the garage till Monday when they open.

2 years old, 30k on the clock.

Turbo blown??

[Paddy1000111]

Sounds like you've blown a turbo pipe off or split it. I've had it on vehicles before and it sounds like a bomb has gone off. Turbos don't go "bang" when they blow, they usually just shit themselves and whine like hell or dump oil into the intake manifold. Start at the turbo and follow all the intake pipes, make sure they're all connected properly and squeeze them and manipulate them to find a split. I've had one on a Skoda that was 1.5cm but enough to give no boost.

 

The rough noise is probably the open intake manifold. They sound like a deep intake warbly noise. 

Edited May 23, 2021 by Paddy1000111

[dig-dug-dan]

52 minutes ago, Paddy1000111 said:

Sounds like you've blown a turbo pipe off or split it. I've had it on vehicles before and it sounds like a bomb has gone off. Turbos don't go "bang" when they blow, they usually just shit themselves and whine like hell or dump oil into the intake manifold. Start at the turbo and follow all the intake pipes, make sure they're all connected properly and squeeze them and manipulate them to find a split. I've had one on a Skoda that was 1.5cm but enough to give no boost.

 

The rough noise is probably the open intake manifold. They sound like a deep intake warbly noise. 

Ok. Hope this is the case as I don't fancy my chances otherwise!

[Paddy1000111]

3 minutes ago, dig-dug-dan said:

Ok. Hope this is the case as I don't fancy my chances otherwise!

Still under warranty isn't it? For a turbo to blow after 2 years/30k something has to have gone majorly wrong. 

[dig-dug-dan]

26 minutes ago, Paddy1000111 said:

Still under warranty isn't it? For a turbo to blow after 2 years/30k something has to have gone majorly wrong. 

Correct. Does a remap count? 😥

[Paddy1000111]

3 minutes ago, dig-dug-dan said:

Correct. Does a remap count? 😥

Don't mention it. If you're lucky they won't know. 

[dig-dug-dan]

14 minutes ago, Paddy1000111 said:

Don't mention it. If you're lucky they won't know. 

I wont, and given the ECU is behind the dashboard, they wont know it's been opened up and fiddled with!

Edited May 23, 2021 by dig-dug-dan

[Paddy1000111]

Well they will if they start doing proper diagnostics with the dealer scanner. The ECU will show it's been reflashed and may not be recognised properly by Nissan Consult. Fingers crossed they will know straight away it's popped a pipe and they will sort it out. I imagine they will plug the laptop in to do an update and clear any codes though as a standard practice which may be an issue. Time will tell... 

[Conor Wright]

Is it a zd 30? If it is its possibly a cracked piston, especially if it's been mapped, mapping a zd30 without changing the mass airflow sensor is dangerous as a dirty sensor can cause the ECU to over boost the turbo which leads to oil vapour being pulled through the system, which tars it up then deposits it in the oil channels up top. usually the turbo gives up before a piston gets starved of oil and cracks. Hence the tales of changing turbos only to have an engine failure shortly after.

If you did change the sensor nissan will see it and void the warranty, if you didnt let's hope they find a physical fault before they plug it in and see the changes.

Garages love people who map things still in warranty. They can wash their hands of it even if the root problem is an over complicated engine that runs way to close to its operating limit.

[Conor Wright]

Re reading that, I worded it poorly, the map is the reason for the increase in oil vapour as the engine "breathes" more heavily. This causes the maf to become dirty, the ecu then has the wrong information and the rest is basically self destruction. 

Obviously if it's not a zd 30 unit this is of little relevance.