Was speaking to a neighbor recently about my problems with Corolla, & he mentioned his 2002 model was treadmill emission tested. Probe placed in tailpipe, car ran on treadmill. Surprised to hear, b/c I thought only OBD I cars (1994 & earlier models) were treadmill emissions tested. Are OBD II cars still treadmill tested in Calif? All of them, or only some?
Did a quick google search. Suggests law changed circa 2010, change saying that OBD II models 1998+ do not require treadmill testing. I expect neighbor is recollecting a test done on his 2002 model performed prior to 2010 law change.
I wonder why it took until 2010 for the politicos to figure this out ? ⊠lol âŠ
Not âtreadmillâ, rolling road testing.
If the place has the equipment it can be done but most states dropped the requirement with OBD2.
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I wonder why Calif seems to still require tailpipe rolling road (treadmill) testing on early OBD II cars, 95, 96, 97? Was there something different about OBD II functionality in those years?
No. No real difference.
My guess is that CA did that because they are crazy.
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We dyno test 1996 through 1999 single-rear wheel OBD2 vehicles
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That is the truest and funniest answer I have seen on this forum to date⊠
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I suspect that some lawmakers donât trust technology, OBD-II included. They probably wanted rolling road testing for all cars. This was a compromise to satisfy enough lawmakers to get it passed in the legislature.
Maryland has the rolling road lines and a few years ago installed a kiosk on the side of the building for OBD-II testing only. You plug the connector into the OBD-II port and follow the directions on the screen. It takes maybe 5 minutes and is about half the price of the tech assisted test.
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+1
AWD vehicles should not be put on a dyno.
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I thought somebody on here said that early OBD II, as in a few years past 1996, did not have readiness monitors. So someone can just remove the battery to pass the test. But I could me mistaken.
Maybe they test for a worn out engine that is burning oil? OBD II wonât detect that.
In PA there are different rules from 1996-2000 readiness monitors: OBDII Readiness Monitor? (Solved) - Belle Haven Shell
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Not sure I understand. Do you mean you treadmill-emissions-test (running on rollers w/probe in tailpipe) rear wheel drive vehicles of that vintage, but you test the front wheel drive vehicles of the same vintage a different way? How? Youâve mentioned befoe you work mostly on trucks. Are you referring only to trucks, or also to passenger cars, sedans, suvâs, etc also?
The California Bureau of Automotive Repair performs an annual study of the effectiveness and performance of the vehicle test program and testing stations. This includes roadside vehicle emissions testing. Pre 2000 vehicles represent the smallest group of vehicles tested but are responsible for most of the pollutants.
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Thanks for doing a little research for the forum to peruse. A few obvious questions ensue:
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Do you mean the pre-2000 vehicles produce the most total pollutants into the air, or that on average a pre-2000 car produces more pollutants than a post 2000 car? If the later, one has to wonder how much total pollutants are emitted by pre-2000 cars compared to post 2000 cars. There are a lot more post 2000 cars on the road, so quibbling about pre-2000 cars may not bring much bang for the buck clean-air-wise. If concerned about air quality, might make more sense to tailpipe test post 2000 cars rather than the limited-OBD II test, focus on that, and to not bother testing pre-2000 cars at all.
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whatâs the difference between asm and tsi testing?
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What does exhaust rog refer to?
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If only obd II tests (no tailpipe probe) are done on 2000+ model years, how do they know the exhaust pollutant profiles & amounts of those cars ?
It says that while the pre-2000 model year make up a relatively small fraction of cars, they produce 70% of the excess emissions
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Total for all cars in that segment, or per car?
Total for all cars. The bars in the graph are total emissions, not per car emissions. On a per car basis theyâre even worse, as you might guess.
What is your basis for that claim? Iâm not saying you are incorrect, but I donât see anything on that page that clearly states it is the total for all cars in that segment. Total for all cars = average pollutants emitted per car * number of cars. The vertical axis on the left isnât clearly defined.
The scale on the left is tpd, or tons per day. No single car is emitting 118 tons per day of emissions, right? Also, the text says â70% of the excess emissionsâŠis attributable to the pre-2000 model year vehiclesâ. Pretty clear to me.
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Why do you think tpd means tons per day? Not claiming one way or the other, but I donât see that nomenclature clearly defined. If it is tons per day, and the OBD II tests reflect the actual emissions levels for post 2000 cars (for which no proof is cited), than the chart makes it pretty clear the pre-2000 vehicles are contributing way more than their share. A lot of ifs tho.
Assuming all thatâs correct, have to wonder how the model years from 1976 - 2000 contribute to the total , year by year. It may very well be that OBD I - 2000 contributes very little to the total.
No doubt the 1970âs car contribute,walking through parking lot the other day, air cooled VW Beetle rolls through , smells like it is spewing raw gasoline.
The text on page 13 reads âtons per dayâ and âReactive Organic Gasesâ.
Print the document and read it in your spare time. There was a lot of testing and analysis involved but remember: they are crazy.
The estimated additional achievable emission reductions for model year 1976 to 2015 light- and medium-duty gasoline-powered vehicles in the Smog Check Program is on the order of 30 to 50
tons per day of reactive organic gases and oxides of nitrogen (ROG + NOx) for 2019.