kajtek1

We've been talking in the past about the risk of DPF delete in states with smog check and I took the risk doing so in Nevada.
Nevada smog include probe and running on the rolls, but they do not plug OBD scanners.
So my car pass the sniff test, (what I did expect) with no problem. Would they plug OBD - it would show "n/a" at DPF and I guess that would be a problem in California, who do OBD check.
The test results don't show any numbers, when couple years ago they would, but what I do care? It passed period.

Towmater

Well, in ca, I can say an adblue canbus delete, will pass. I believe it's only looking for a visual inspection that everything looks normal. When I went last they pretested it a cheap obd pulg to see if the monitors were set. That adblue monitor was set as n/a, so it showed the same as ok, as it passed.

I would think the same for a dpf delete. Also, did you take both the cat and dpf out? They are in the same box and it's hard to just chisel out the dpf portion without dislodging the cat.

kajtek1

On this engine cat and dpf are in the same housing. When I was chiseling the stuff out, front 20% had different honeycombs than the rest, so I assume that was the cat portion.
Not a big difference thought.
Now I heard that California changed the smog laws for newer cars and depends on MY they will pass even with 2 failed features.
I did last California smog a year ago and my impression that technicians have no idea what they see under MB hood did not change.
That said, NV technician open the hood as well. Same impression

artim808

In CA:

• Gasoline Vehicles
  • 1996-1999 Gasoline Vehicles can have 1 monitor not-ready
  • 2000 and newer gas vehicles must have ALL monitors in a ready state with the exception of the EVAP monitor.
• Diesel Vehicles
  • 1996-2006 Diesel Vehicles can have 1 monitor in a not ready state.
  • 2007 and newer Diesel vehicles can have 2 OBD2 monitors in a not ready state

Etienne Lau

I can't think of any states, that actually spent the extra money needed to purchase proper Diesel testing equipment. Some states, just state diesels are test, other states don't test diesels. For the states that say they test Diesels, I doubt they actually test for true diesel emissions at the tail pipe. Which is why I for one think this entire Dieselgate thing is such a scam, no one actually test real diesel emissions on passenger vehicles. And the number of passenger diesel vehicles in the US are so small relative to on highway Diesel Trucks. The emissions produced by these Diesel passenger vehicles are minuscule.

kajtek1

I would have to dig old smog results, but I thing NV sniff test is checking CO emission.
I don't think there is any equipement who can check particles. What is the car will start regeneration during the test?
Diesel tests, at least in California were triggered by pickup owners, who tuned factory 250 HP engines up to 1000 HP, obviously having no regards to emission or noise levels.
So checking EGR and mufflers on trucks is primary goal for the law.
MB diesel owners got sideswiped.

Etienne Lau

Here is a document for diesel testing in Nevada: https://dmvnv.com/pdfforms/ec4.pdf

They basically stick a opaque material in front of exhaust to see if it picks up any visible particulates.

kajtek1

Nice find. I just learned that it is not Nevada smog, but Clark County smog. Clark County is basically City of Las Vegas + CIty of Henderson as county border is about 20 miles from the Strip.
Washoe County is Reno, what leaves about 90% of Nevada not having smog tests (something to think about)
But now I read that the probe is opacity tester.
So either my MB is so clean that it doesn't emit particles even with DPF deleted, or the opacitor does lousy job.
I hope it stays that way, no matter what it is.
EDIT. I found smog results from year ago, when car had working DPF. Opacity number was 0.8%.
New test is not giving the number, only PASS.
Can't find much info about opacity testing, but California for heavy diesels allows 5% , what is new number for 2019

kajtek1

MY BAD
I had more time today and read the smog results again.
So there is a number of opacity with DPF delete. I did not notice it the 1st time becouse the number was 0 (ZERO).
So how the car with working DPF makes 0.8 opacity, when with DPF delete makes 0 ?
Beats me.

artim808

Maybe faulty test equipment?

kajtek1

The only difference before test was, that if my memory serves me well, the 1st time I drove to smog station straight from the house, what is 1.5 mile, when the 2nd test was done after driving few miles.
Each measuring equipment has its measuring tolerances, but zero is zero.

listerone

Isn't modifying pollution related equipment in any way a violation of Federal law????

kajtek1

It is murky subject. Federal law forbids deleting the equipement, but than states allows for passing the test with 1 or 2 pollution items "not ready".
I used to drive 1980 Chevy El Camino, who never passed California smog without putting few hundred$ in it. Finally took it to state referee and got legal exception as the law can't force citizens to put big money into old car only to be pollution compliant.
Than, when the car with deleted DPF pollute less than with working DPF......

Etienne Lau

It is a grey area. It's done very blatantly by all the diesel pickup truck owners that make a big thing about rolling coal. Hard to enforce as no one really knows what to look at and check during annual inspections. In some states, there is no pollution/emissions checks. And it varies depending on where one lives in certain states.