Nissan 2005 Patrol wagon

[Kapie]

Good morning to all smart Nissan drivers.

I have a 2005 Nissan patrol, 3l turbo diesel wagon. 

After about 40-45 minutes of driving it looses power with a lot of black smoke coming out of the exhaust.

Then if I turn the engine off and let it sit for a few minutes it goes again only for the process to repeat itself.

Funny enough that it doesn't seem to affect the revs on the engine when it does this.

Any ideas please.

Thank you

[Rumcajs]

G'day, welcome to the forum.

The black smoke is usually a symptom of overfuelling.

You can start with the basics, air cleaner, fuel filter etc.

This seems/appears to be something related to engine sensors or and ECUs as when you cycle power off everything resets.

Are there any error codes/MIL flashing when that happens?

Do you have  themeans of seeing engine sensors output?e.g. via ECU Talk software and interface cable?

I'm being tempted to suggest perhaps MAF sensor is playing up....

Anyway as a part of investigating you could try

When it happens don't turn the key off but check if you can at stationary and engine still running use acc pedal to run up max RPM e.g. floor it to see what happens. 

Also what is the lack of power demonstrating as?

No revs, lack of available throttle response or just lazy going?

Also what engine mods if any do you have?

Regards

 

Edited July 22, 2018 by Rumcajs

[Kapie]

Good morning

Thank you for replying so quickly.

You make a good point about fuell over  flowing. After about 45 min driving she looses power up to the point where I have to pull over and then in neutral she will get to up to close 5000 revs but with black smoke. If I then turn her off and let her sit for a minute or so she comes good again. Only to play up later again. So it makes sense about what you said about the system resetting itself. I should actually change fuell and air filters as they are long overdue. Can it be that?

Bear with me please as I'm a electrician and not a mechanic so I'm limited in that regard. I can help myself with the basic to middle of the road stuff but I'm no good after that. 

And don't have any engine mods just a electric brake for towing heavy stuff.

So to sum up: After driving for about 45 min - 1 hour she loose power and becomes very lethargic. Then I have to pull over. In neutral she gets close to 5000 revs but lot of black smoke. I turn her of and wait a minute or two. Then she goes again but +-45 later same thing happens again. 

Thanks for your help so far.

Regards Ben

 

[Rumcajs]

G'day,

Every logical explanations points to not being the air cleaner or fuel filter, however I do recommend to inspect and change as contaminated air cleaner will foul MAF sensor and contaminated fuel filter will ruin the fuel system and indeed ZD30 of 2005 and earlier vintage has a very weak and fragile injection pump which doesn't tolerate such issue very well and for long.

So, if the engine doesn't seem to labor or appears under heavy load like after the fault occurs (hence how it freely revs up stationary) we can discount exhaust blockage (sometimes exhaust catalyst can be faulty and as it heats up it can collapse and cause exhaust restriction which is usually manifested by lack of power and a lots of black smoke. But that wouldn't clear after 1 minute engine off scenario either....

However to be able to actually do any diagnosing you do need to see what the engine is doing, e.g turbo boost at the point of failure, engine sensors reading (MAF voltages vs RPM vs TPS position)

So in the case of turbo boost there is clear relationship between power output, smoke output so if the values don't support healthy operation one can start pin point the probable cause.

Because your vehicle is stock it will be very difficult without an access to engine telematics to ascertain anything.

The only thing you can do is to check under the hood when stationary and even then only visual checks.

This what I would do if it was happening to mine, and  I do have ability to read engine sensors on the fly and have extra boost gauge and exhaust gas temperature probe and gauge installed.

Using ECU Talk LCD interface I would scan boost pressure and MAF voltage vs TPS% and turbo actuator% and injection pump timing solenoid% while also observing EGT temps.

Low boost will increase EGTs under heavier load and I will also be able to see MAF voltages and be able to deduce if there is an issue with either system.

As an example faulty MAF signalling can affect the way ECU controls fuelling and that in effect can cause smoke, lack of power etc.

I would change air and fuel filters, run engine at the idle when there is no issue and check the VGT actuator (turbo) is fully up and re-check it again when the failure occurs ( this could indicate that either the control system is malfunctioning, or there is vacuum leak under the specific conditions.)

I would check and also disable either temporarily or permanently the intake swirl control circuit just in case it accidentally jams closed restricting the intake (which can have the effect you're experiencing.) 

Another step I'd do would be to disable EGR circuit to see if that is playing up however that opens up another can of worms for those who don't grasp the concept.  Faulty EGR valve which fails to close intermittently can cause similar symptoms you are experiencing.

Basically something is interfering with proper way the engine air induction, fuel quantity and exhaust extraction is functioning. 

It  could be either wrong input causing wrong output (or bullchit in bullchit out) or intermittent failure of control circuit for either of those systems.

Regards

 

 

Edited July 26, 2018 by Rumcajs