Nissan X-Trail Non-start Timing Chain?

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Fat Freddy
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Re: Nissan X-Trail Non-start Timing Chain?

Post by Fat Freddy »

What I can say is a stretched Nissan chain, even when it starts will cut out. Fuel, spark??
the customers mechanic who replaced the head gasket says it wont be.
Coarse he did. The statement was probably proceeded with "What's he checking that for? I've already done it".

I'll be surprised if it is not chain related. But with out a known good for that exact engine or further inspection we can only assume.

naveen147
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Re: Nissan X-Trail Non-start Timing Chain?

Post by naveen147 »

What turned out to be the problem? Was the timing off?

Chris76
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Re: Nissan X-Trail Non-start Timing Chain?

Post by Chris76 »

Hi, did you happen to figure out what the problem was? I have a 2005 XTrail with the exact same problem - would only start with crank sensor disconnected. Once started, it ran smoothly aside from being slow to respond to depressing the accelerator and return to a smooth base idle. Aside from that - the engine was as smooth as silk, would rev and hold revs like normal.

Once it was running, I let the engine warm up completely then turned it off, and reconnected crank sensor - not expecting it to start. Then it started again and now is starting perfectly as per normal. All engine functions are as before - perfect.

This would suggest it is NOT a timing chain issue. Any clues?

Any help is much appreciated. Chris

Technician
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Re: Nissan X-Trail Non-start Timing Chain?

Post by Technician »

I don't know, but it comes across to me like an electrical fault. Because the engine will not start cold with the crank sensor connected, but will start with it connected when warm, suggests to me that resistance of some component is high when cold, thus current cannot flow, but when warm the resistance has dropped and now current flows.

What about a code read and live data to start?

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vasek
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Re: Nissan X-Trail Non-start Timing Chain?

Post by vasek »

Hi.
Feature of the NISSAN control unit is, that when the crankshaft sensor is disabled,
the controller operates in emergency mode.
Only the camshaft signal is used for synchronization.
This can be achieved due to a specific signal from the camshaft sensor.
Each cylinder number corresponds to the number of pulses in the camshaft signal packet.
At the same time, there is no VVT control, there is a power limit, and the engine start is delayed by time.
.
In the example from the first message in this post , there is a very significant backlog in the position of the camshaft sensor from the crankshaft sensor.
The difference is 13 degrees.
Synchronization of the shafts is broken.
Two signals start knocking the controller from working correctly.
The reason is a stretched chain.
.
The manual says that the permissible difference in the camshaft position is 5 degrees.
In practice, the tolerance can reach 10 degrees.
If the camshaft pulse drop fits into the gap between the crankshaft pulse packets,
the controller is able to correctly control the injectors and coil drivers.
If the difference reaches a higher value, we get the code P0340, chaotic driver management.
Or complete absence of control signals.
.
So you need to show the signal that is present in Your case.
Attachments
TOLERANCE.PNG
SYNC NG FROM POST.PNG
SYNC OK.PNG
DATA.PNG

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Fat Freddy
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Re: Nissan X-Trail Non-start Timing Chain?

Post by Fat Freddy »

Chris76 wrote:
Fri Apr 24, 2020 8:01 am

This would suggest it is NOT a timing chain issue. Any clues?

Any help is much appreciated. Chris
"NOT", why not?

To me screams timing chain. Put the scope on hot and cold and you will see why. Look at how the tensioner works.

HarleyMike
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Re: Nissan X-Trail Non-start Timing Chain?

Post by HarleyMike »

My thoughts. 2.5L Nissan Altima for reference.
Attachments
X trail with reference.psdata
(2.11 MiB) Downloaded 316 times

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