2009 CRD - EGR Block

[apalsson]

All,

The subject of blocking EGR has probably been done to death in various threads but I am probably too lazy to troll through all the info in various places for an answer to what I need to know so a single thread would be very handy for me :)

My Patrol is a 2009 manual CRD and I have recently bought a van that weighs up to 2.3 tons fully loaded and I am concerned about EGT temperatures when towing, especially sky high EGTs. I have a Scangauge but because budget is a bit tight at the moment, I haven't bought a Pyrometer yet. Recently, I have had issues with black smoke on acceleration but am suspecting that is either due to the MAF sensor or even sloppy work on valve adjustments during recent 60km service.
Can will go into Nissan for 70k service in a week or two and I am going to ask them to diagnose this for me (I have found Nissan here to be reasonably good with service)

As a "poor mans" method of reducing EGT, I am thinking about blocking EGR to try to reduce exhaust temperatures somewhat.
Would that not be likely to achieve some reduction in EGT?
I understand the turbo might spool up a bit quicker and possibly spike a bit higher but have also read that the ECU in the CRD models manages boost better?

Would it be safe to only add an EGR block without other mods (except the Scangauge to keep an eye on boost)?
Wouldn't I be likely to blow more black smoke with blocked EGR?
Are there other unwanted side effects?

[the evil twin]

My '07 showed some boost 'spikes' on the scan gauge after I blocked EGR.
Rather than fit Dawes and Needle valves I chose to use the other method and adjusted the Turbo Actuator.
It is a bit fiddly but works quite well and is detailed in the ZD30 Reference Manual.

Blocking EGR is mainly used to reduce particulate matter and oil contamination.
Blocking has no effect at high engine loads as the EGR is normally blocked by the ECU then anyway.

There will be a smalll increase in 'black smoke' after EGR block

Side effect is increased NOx pollutant levels

You can expect to see P0401 codes on the Scangauge if you block the EGR completely
No biggee just clear them as they don't cause limp mode.
If you do get limp mode it is because of boost issues and you will need to adjust the Turbo Actuator or fit Dawes gear

If you are after reduced EGT's when towing then you would get better results with a more efficient intercooler.

[the evil twin]

... should also have added.

In researching EGR and the effect it has make sure you compare apples to apples.

EGR on a petty is a totally different critter to a diesel and EGR on the Di's is again different to the CRD.

The CRD has a heat exchanger on the EGR manifold and the ECU and EGR valve operates differently to the Di's.

[apalsson]

ET - as usual, I think you are right :)
To avoid any guesswork, I have ordered an EGT gauge. Maybe off the cheaper end but not the absolute rubbish end. I guess the inevitable consequences of any mode I make will be based on anecdotal evidence rather than facts unless I have a way of seeing for myself how the engine reacts to changes.
I can monitor boost through the Scangauge for now, even though I would have preferred an analogue display rather than the digital readout. Analogue boost gauge will be next on the list and after that, we can start thinking EGT block, bigger exhaust etc.
The intercooler shows no signs of leaks or other problems so I will probably just flush it out for the time being

[the evil twin]

If/When you fit the EGT gauge don't have a cow if you see 600 plus degrees esp when towing.
That is what the CRD's run at out of the box.

Now that I have sold my CRD wagon one of the things I really miss is the Scangauge... Jeez they are a handy bit of kit.

Can't use one on the Ute with the 6.5 Chevy engine tho, the fuel consumption would just read off scale high and there are no fault codes to check

[apalsson]

If/When you fit the EGT gauge don't have a cow if you see 600 plus degrees esp when towing.


Mate, I'm too old to have "anyting" and especially cows :)