OPINIONS: Removing CAT from D40 2.5td auto

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Everyone I talk to says throw on a hiflow Cat and 3" dump pipe, and take to the DPF with a screw driver and replace it back with the guts removed. The DFP sensors don't know anything is wrong (so I have been told). And a visual inspection looks 'normal'. I will find out one day.
 
The sensor before and after would read pretty much the same. Since the regen cycle and limp modes are only initiated when the "after" sensor reads a lower pressure than the "before", taking away the source of the differential would completely avoid either procedure being initiated by the ECU.

The tell-tale will be black smoke from the exhaust when accelerating, climbing etc, plus a negative and not-so-immediate on the lifespan of koalas, budgerigars and zebra finches (among other creatures). If you can live with that, your screwdriver exercise may save some trouble later on.
 
Removing the DPF is illegal, so mum should be the word.

Watch the sensors before and after - the ECU monitors those to see if there's a pressure differential and if there is, it triggers a regen cycle (injecting diesel into the chamber during the exhaust stroke of the cylinder). If there's enough differential, it will put the vehicle into limp mode.

Old Tony, I don't believe it is 'illegal'. I have had a bit of trouble with my DPF (i hate Nissan with a passion) and having done a lot of research and had discussions with numerous, so called, experts i'm lead to believe the DPF is installed in the auto D40 to conform to Euro emission standards, not aussie emission stds, which aren't as stringent.

Now warranty is a different matter. Nissan will can any warranty claim if the DPF is modified in anyway. And this probably includes if the rear diff falls off. They'll blame the mod (have i said i hate Nissan with a passion).

I stand corrected if i'm proved wrong but that's what i've been told. And some of those, so called, experts are from Nissan warranty WA. Go figure!
 
There's a federal law that states you are not allowed to tamper with or remove *any* fitted emission control devices and the fine apparently *starts* at $25,000.

I'm trying to discover more about this now, I'll edit the post to update it. Searching through Austlii database can be painful sometimes.

Here's one piece of legislation that could cause trouble.

Motor Vehicles Standards Act 1989
Part 3, Division 2, Section 13A

(1) Subject to subsection (3), a person must not do an act that results in
the modification of a standard vehicle in a way that makes it nonstandard.
Penalty: 120 penalty units.

Subsection 3 is about getting written permission directly from the minister.

1 penalty unit = $110, so the fine for this breach is $13,200 on its own. I'll find more later.

Just as an aside, this section of the ADR actually applies to any vehicle modifications, including tyres that go outside the size range specified, headlight wattage and colour, tail light fixtures, rear-facing lighting, number of forward-facing white lights - the list goes on.

If they want to get really nasty with you, the book they can throw at you is extensive and heavy.

The search continues for specific emission control legislation. It's a big read.
 
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he sensor before and after would read pretty much the same. Since the regen cycle and limp modes are only initiated when the "after" sensor reads a lower pressure than the "before", taking away the source of the differential would completely avoid either procedure being initiated by the ECU.

I would think the before sensor would sense a higher pressure (DPF fouling) and force a burn.The aft sensor would always read lower as DPF is a restriction. Could be talking about the same thing .High pressure before means lo pressure aft.
 
Hey guys its been a long while since I have been on and I have some news. In regards to cat and dpf let's say 3" all the way lol.. Dump pipe straight through, wasn't easy tho had a lot of hurdles to jump over but I got there.. I had to get all the exhaust made up and purchased a dump pipe for $150. Then for the hard part spacing the O2 sensor out with a custom made bung by a engineer to suit the stupid thread that they have.. Then I had to get all the fittings made up to relocate on the new pipe around the same place the old ones were.. After a ecu reset its been about 1 year now I haven't had a forced dump burn so I guess it worked.. I will post some pics up of what it looks like when I get the chance.. Cheers guys
 
apart from the legalities of removing the cat etc.

I have a manual, what would be the possible engine concerns I should have if I was to remove the cat.

I have a cat back 2.5" exhaust with a tiny muffler. Would I just need a pipe from the turbo to connect with existing exhaust (replace factory dump pipe & cat).

What effect would it have on performance and the longevity of the engine?

Will this combo give my Navara that tuff diesel note?
 
apart from the legalities of removing the cat etc.

I have a manual, what would be the possible engine concerns I should have if I was to remove the cat.

I have a cat back 2.5" exhaust with a tiny muffler. Would I just need a pipe from the turbo to connect with existing exhaust (replace factory dump pipe & cat).

What effect would it have on performance and the longevity of the engine?

Will this combo give my Navara that tuff diesel note?

any feedback, advice?
 
apart from the legalities of removing the cat etc.

I have a manual, what would be the possible engine concerns I should have if I was to remove the cat.

I have a cat back 2.5" exhaust with a tiny muffler. Would I just need a pipe from the turbo to connect with existing exhaust (replace factory dump pipe & cat).

What effect would it have on performance and the longevity of the engine?

Will this combo give my Navara that tuff diesel note?

Well it's illegal, engine dramas? No not really and performance maybe a little more responsive.. As for the note yeh it's loud :)
 

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