Utah Diesel Emissions Testing - What's Up?

[gmog220d]

I will be moving to the Salt Lake City area later this year. I am curious about what diesel emissions testing is like there, and there's not a lot of info online. And apparently Utah's rules have changed/gotten tighter this year (2015)? Just my luck . . .

The vehicle in question is my '74 240D. Looks like it'll be getting tested yearly. What does this test entail? How strict is it? What are the standards?

The car starts and runs well hot or cold. I just went through and set cam and injection timing. It's about to get the injectors pulled and tested/calibrated, before we move.

What are we in for over there? Shall I begin bending over? All my vehicles are old, and they all will have to be tested, something I've avoided here in New Mexico.

[mannys9130]

Utah Smog Check and Car Inspection | DMV.org

It doesn't say what the pre OBD diesel test is, bit if it's like Tucson AZ it's simply an exhaust opacity test. Here, they run the car on a dyno up to 35mph and use an optical sensor to measure how opaque the exhaust ploom is. The limit is 20% and I have gotten 1% on both my 84 and 85 for years now. They're NA, so not preboost smoke puff even.

My most in depth test was just a registration check, quick underhood check to look for defeated or removed EGR valves or smog pumps, and the opacity test. Mostly they don't do anything beside test opacity and check the VIN.

We don't have inspections here though. If your car is road worthy you're probably fine. Horn, brakes, mirrors, lights, etc. I don't know how it is there, but in Massachusetts if you had a car that was in good shape and you went to get it inspected, you left something easy like a burned out light bulb or torn wiper blades for the shop to catch. They made a little cash and they wouldn't look to hard if the car was pretty road worthy. Now if you took the car in and already repaired everything, they'd startvlooking real hard for safety concerns. Really piss off the inspector and he'll say the car's too rusty to be safe and fail you on the spot. So stupid.

[gmog220d]

Thanks for the reply and for the link.

If it's a 20% smoke opacity test I should be fine. This car runs well and doesn't put out a lot of smoke. I'm not worried about the safety inspections - everything works well. We had that back in TX where I grew up and I kinda like having more cars on the road with working signals and horns, and brakes.

Still curious to hear from someone in UT who's got diesels that are tested.

[BillGrissom]

Thanks for relating. Since we don't have any emissions tests on older diesels where I live in CA (not even when selling), I assumed there weren't any in the "red states". Not that it is a bad idea. I don't believe the old line about diesel smoke being harmless.

[Orv]

Most important thing for opacity testing is to rev the engine a couple times right before you pull in for the test. Otherwise all the soot you accumulated idling in line will come out when they do the test, giving an artificially bad score. (No experience with UT, but they used to do it in WA.)

[uberwasser]

The opacity tests should be something you pass with flying colors, unless there's something seriously wrong. Like Manny points out, the limit is pretty high (I believe it's actually 30% here in AZ). I frequently blow fractions of a percent especially when using biodiesel. In the ballpark of 0.2%.

[gmog220d]

Originally Posted by uberwasser

The opacity tests should be something you pass with flying colors, unless there's something seriously wrong. Like Manny points out, the limit is pretty high (I believe it's actually 30% here in AZ). I frequently blow fractions of a percent especially when using biodiesel. In the ballpark of 0.2%.

Cool. I'm feeling better about this. The car runs pretty good so it should be fine. Thanks for the response.

[801mbz]

IM is by the county. Salt lake doesn't test. Antique plates do not test. I work on old MB. I have parts cars. 801 973 4467.

[gmog220d]

Thanks for posting, 801mbz. I'll check out the antique plates option for the '74, if it's old enough. We're in Cottonwood Heights, BTW, 84121.