There is more than one DPF code...
Sensors can be checked easy enough by looking at the live data.
- Thread starter ukracer
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Sensors can be checked easy enough by looking at the live data.
AVI_8
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The pressure differential will likely be detected and will be showing a DPF fault if it’s blocked.
If it’s that badly blocked, there are company’s now who can connect it up to a machine in a tank and send high pressure pulses of water/cleaner through it to unblock it.
This after you’ve got to the point of diagnosis to determine the reason the re-gens stopped in the first place. Hence the accurate reading of codes and testing sensors.
If it’s that badly blocked, there are company’s now who can connect it up to a machine in a tank and send high pressure pulses of water/cleaner through it to unblock it.
This after you’ve got to the point of diagnosis to determine the reason the re-gens stopped in the first place. Hence the accurate reading of codes and testing sensors.
James1979
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Interpreted that wrong
???
Ironically the Dpf light came on when we remove the exhaust DPF back...
8ob
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With a vac/pressure pump and a meter. They dont throw a code they are really just switches, ecu throws up the codes.
Any more detailed info Bob. We do have one of those.With a vac/pressure pump and a meter. They dont throw a code they are really just switches, ecu throws up the codes.
The whole thing is doing my head in....
The OBD2 codes don't say there is a 2002. But auto assist shows 2002 not 2001... arrgg.
A google for P2001 is suggesting a NOx or EGR DTC. But I thought P2xxx codes should be generic.
This vehicle shouldn't have a NOx sensor, but EGR could be related to a blocked DPF.
I'll have a look on our tech data at work on monday, to see what the official Nissan description is.
P2002 is either the DPF is still being detected as blocked, or there's a fault with the pressure sensor.
If it's a differential pressure sensor (were there two small pipes/hoses going from the DPF to a sensor?), check the hoses been reconnected the correct way around.
Or it could be a simple exhaust pressure sensor (single pipe/hose to a sensor, which will often be mounted nearer to the turbo).
Given the history, it's probably worth taking the hoses off completely, and checked that they're clear.
A quick look at live data, will soon show if the values are plausible.
If the value goes negative, the hoses are likely to be the wrong way around, but if it's near zero with the engine off, and gradually rises as the engine speed increases, it's likely a blocked DPF.
An application of some controlled pressure to the sensor (via the hose from the upstream side of the DPF), to see if the value is accurate, will tell you if it's a sensor or DPF issue. (you really want a Mityvac, as you only want to gradually apply 10-15psi max in a controlled fashion, to see the live data value is similar).
This vehicle shouldn't have a NOx sensor, but EGR could be related to a blocked DPF.
I'll have a look on our tech data at work on monday, to see what the official Nissan description is.
P2002 is either the DPF is still being detected as blocked, or there's a fault with the pressure sensor.
If it's a differential pressure sensor (were there two small pipes/hoses going from the DPF to a sensor?), check the hoses been reconnected the correct way around.
Or it could be a simple exhaust pressure sensor (single pipe/hose to a sensor, which will often be mounted nearer to the turbo).
Given the history, it's probably worth taking the hoses off completely, and checked that they're clear.
A quick look at live data, will soon show if the values are plausible.
If the value goes negative, the hoses are likely to be the wrong way around, but if it's near zero with the engine off, and gradually rises as the engine speed increases, it's likely a blocked DPF.
An application of some controlled pressure to the sensor (via the hose from the upstream side of the DPF), to see if the value is accurate, will tell you if it's a sensor or DPF issue. (you really want a Mityvac, as you only want to gradually apply 10-15psi max in a controlled fashion, to see the live data value is similar).
jsf55
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A little google by me might help ? https://www.yourmechanic.com/articl...iency-below-threshold-bank-2-by-jamahl-walker
I couldn't find any other reference to it other than, NOx Trap Effeciency below threshold bank 2, from the tuning stuff i use
I couldn't find any other reference to it other than, NOx Trap Effeciency below threshold bank 2, from the tuning stuff i use
AVI_8
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What are the common causes of code P2001?
- A defective or overloaded NOx trap or NOx trap element
- A malfunction in the diesel exhaust fluid injection system
- Inadequate NOx reductant fluid
- Inoperable exhaust gas recirculation system
- Severe exhaust leak upstream of the NOx trap
You guys beat me to it, looks like it’s pointing to blocked DPF, possibly caused by an EGR problems, are there any stored EGR codes?
premmington
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Want my input! Here goes!
Mapping - don't do it! If you think - someone with a laptop and half an idea - has more computing power than the manufacturers - stop kidding yourself. What you get from the factory is - the most performance/economy/reliability money can buy in one equal package.
Mapping - comes into its own - for dropping faultscodes off P tables to hide faults on old cars.
--------------
Now comes the future: Three year old cars with problems on retail car sales sites (money to be earned). Faults dropped off tables - to get get cars sold - without warning lights on. Diagnostic prospects zero for the next fault. I kid you not....
OH yes is it happening.... Sorry!
I was interested why someone suggested you might have a view.Want my input! Here goes!
Mapping - don't do it! If you think - someone with a laptop and half an idea - has more computing power than the manufacturers - stop kidding yourself. What you get from the factory is - the most performance/economy/reliability money can buy in one equal package.
Mapping - comes into its own - for dropping faultscodes off P tables to hide faults on old cars.
--------------
Now comes the future: Three year old cars with problems on retail car sales sites (money to be earned). Faults dropped off tables - to get get cars sold - without warning lights on. Diagnostic prospects zero for the next fault. I kid you not....
OH yes is it happening.... Sorry!
I wondered if you was an engine tuner but it sounds like you are not in favour of it. I would normally agree with you but for the fact we know a few tuners who make a living on mapping race cars.
And there is also the emissions debacle with VW and others.
The fact a new DPF is over 2k means it's very lucrative to fit one knowing the buyer will have to shell out not Nissan when it blocks.
I can buy a new Truck for 3.2k. Lol
Thanks for your reply though. I am not keen on mapping it out but I can't find a second hand DPF and Billcar Nissan are saying that new ones give even more problems.
Plus they don't come with new sensors.
Seems like I can't win.
premmington
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I was interested why someone suggested you might have a view.
I would normally agree with you but for the fact we know a few tuners who make a living on mapping race cars.
And there is also the emissions debacle with VW and others.
The fact a new DPF is over 2k means it's very lucrative to fit one knowing the buyer will have to shell out not Nissan when it blocks.
I can buy a new Truck for 3.2k. Lol
Thanks for your reply though. I am not keen on mapping it out but I can't find a second hand DPF and Billcar Nissan are saying that new ones give even more problems.
Plus they don't come with new sensors.
Seems like I can't win.
Don't buy a diesel - Euro 4/5/6... Is my advice....
500e
Always buy fire insurance a flood is a hard start
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premmington
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I was interested why someone suggested you might have a view.
I would normally agree with you but for the fact we know a few tuners who make a living on mapping race cars.
And there is also the emissions debacle with VW and others.
The fact a new DPF is over 2k means it's very lucrative to fit one knowing the buyer will have to shell out not Nissan when it blocks.
I can buy a new Truck for 3.2k. Lol
Thanks for your reply though. I am not keen on mapping it out but I can't find a second hand DPF and Billcar Nissan are saying that new ones give even more problems.
Plus they don't come with new sensors.
Seems like I can't win.
Your quote " I can buy a new Truck for 3.2k."
No you can't - you will buying a used high mielage truck for £3.2k
The reason they sell new trucks for new RRP money is: Old ones wear out and need replacing.
The money car wise is best lost "at the top of the tree than the bottom of the tree"
What's the difference between testing then @Ruffian ?
My son has a photographic memory and picks things up quickly.
Som of these packages offer training and he's not about to drop a remap on his GTR his tuner will do that.
I fully appreciate the comments from members that you can do damage if you don't know what you are doing. That said everyone had to start somewhere or you will never learn.
It's quite funny as I am admin on a sublimation forum and I constantly see comment like " I want to start sublimation so can you tell me how to do it."
To be met by members replying "you need to do some research first" now I know a fair number of those replying knew nothing about subbing when they first joined the forum. Lol
Hence my researching various places and asking some silly questions.
Fuel Rail pressure from petrol to diesel is vastly different.
Like 4 bar on petrol and 15bar on diesel (can be alot more also)
