DIY emissions analysis

[Capriciouss]

The University in NC does emissions testing with a gas analyser and obd2 logging rigged up in vehicles for portable use. I assume they are running the gas analyser on an inverter. They use a separate battery to run the equipment so that it is not loading the system other than the extra weight. I am also looking for a cheap gas analyser, preferably 5-gas to emulate their setup. Texas inspection stations still use 4-gas units, leaving out NOx. I bought a DashDyno for obd2 logging, though I haven't gotten it to log anything to the sd card.
It's surprising to see anyone else interested in emissions testing who isn't directly involved in the industry. I created a gas additive and want to get a handle on what's going on with it before spending the $27k for FTP-75 Stage 1 testing. I was very put off by the attitude of the engineer I talked to at one of the EPA approved facilities in TX, as he was bragging about the test only taking 11 minutes. You have to do 3 before and 3 after tests on 2 vehicles for stage 1, minimum. 2 hours and 12 minutes for $27k... am I in the wrong business?!!!

[Dad and Dotter]

Howdy Capriciouss!

Seems like for 27K U$D you could buy your own equipment to certify the product!

Been looking more at the diesel side of things the past few days. Quite interesting. One of the new laser smoke meters can be had for about $1100, which of course I do not have. I'll keep looking for cheaper. Would love to be able to afford to buy instead of make-- more time for testing.

Photometers with an accuracy of +/- 0.5% and a sampling rate of twice per second can be had for about a c-note. Choosing a light source (perhaps a skelkwank diode) is the next chore in designing a homebuilt diesel smoke opacity meter. A calibrated scale can be made with known density optical filters.

Not sure whether I should use a smoke chamber or not. If you do, you have to keep a temp of 100C to prevent condensation in the chamber.

Why would I go to the trouble of all this? Gandhi, one of my heroes, said that we should be the change we wish to see in the world. I told you I was a control freak.... and like I said before, my automotive technician daughter got me into this. I'm giving her something that she can use in her own business, which she wants to have instead of working for someone else.

Guess you better throw me in the watering trough for unicorns over in the unicorn corral. I'm sounding kind of new-agey here.

[Dad and Dotter]

RE: UNC

WVU has the EERL, engine emissions research laboratory. I haven't been to their website, if they have one, yet. I'm sure they must have done some interesting research. I read about their work and it said that they put together some of their own equipment systems from components.

Old Dad's back in school and I wish I had more time for class!

[Capriciouss]

EERL was the one I was thinking of that has the mobile setup. IIRC the Prof. in charge says it's "Energy in equals .x energy out", which is a good rule of thumb, when you don't consider catalysts. He didn't return my call. The official lines of the EPA and FTC seem to be that gas additives do not improve mileage. That might be because the testing they require is so expensive - not less than $54K to put 2 cars through the FTP-75 tests, Stages 1 & 2 - last time I looked. That cuts out a lot of inventors.

You can closely simulate their testing (sans dyno) simply by using a mobile setup like EERL's. They are using the pistol-grip style probe up the tailpipe, hose run through the car window. The DashDyno will log up to 16 obd2 items, including external GPS (though I'm not sure it does elevation) and has been used by universities in studies. Presumably the gas analysers have a serial out for logging to a laptop or whatever.

Let us know about the opacity meter project progress!

[Diesel_Dave]

FYI, most of the newer diesels (with SCR systems) have onboard NOx sensors. I'm not sure the exact cost, but they're comparable in technology with an O2 sensor. I see some used ones on eBay for $50:
05 12 GL ml R Class Nox Sensor Brain Module Harness Nock Knock Exhaust | eBay

As far as CO goes, you might be able to modify a CO meter that's used for environmental safety (like near furnaces). I think they're fairly cheap.

You might also be able to do something similar with CO2. I know some industries (like breweries & greenhouses) have little meters for safety, however, I'm not sure if they'd read high enough for exhaust gas.

CO2, however, is one thing you can get quite accurately from fuel consumption because it's a major product of combustion. Same goes for O2 on a diesel.

With these meters you'd have to do something to cool the gas before it gets to the meter, because it likely won't be able to take the heat.

[Dad and Dotter]

Does anyone else think that it might be a good idea to ask some folks from EERL or CARB to participate here?

I've decided to contact them, in any case. I can invite them here if anyone else is interested. I don't think a few more connections in the world-brain will hurt anything....

[Dad and Dotter]

Have decided to buy my first piece of automotive test equipment-- an ELM327 OBD-II laptop computer interface. $10 from a top-rated seller on the giant auction website.

The ST1119 IC is said to be better, but only one place I can find sells a finished module and it's $60. I'm not ready to devote a lot of time to a soldering iron if I can avoid it. I know I'll have to, but every piece of equipment I can buy, I will.

[Capriciouss]

Originally Posted by Diesel_Dave

FYI, most of the newer diesels (with SCR systems) have onboard NOx sensors. I'm not sure the exact cost, but they're comparable in technology with an O2 sensor. I see some used ones on eBay for $50:

Great idea! I had forgotten that some cars had those. Should easily connect to DD's analog input. Very interesting.

[Capriciouss]

Originally Posted by Dad and Dotter

Does anyone else think that it might be a good idea to ask some folks from EERL or CARB to participate here?

That would be GREAT!

[Capriciouss]

Originally Posted by Dad and Dotter

Have decided to buy my first piece of automotive test equipment-- an ELM327 OBD-II laptop computer interface. $10 from a top-rated seller on the giant auction website.

I bought an ELM327 USB interface first as well. The software included was good for reading codes, but not logging. Good software for it was about $150.

Then bought a Bluetooth interface to use with the Android Torque app, but it wouldn't connect to the obd2 on my Ford.

Then I bought another BT adapter for $9.99 last month and it would pair with my Archos 101, but not connect with it. AARGH!

That's what I get for trying to "cheap out".

I did figure out how to get the DashDyno to record. It was necessary to create a dyno file and AUTO_REC.sc to get it to record (log) automatically.

The ScanGuage won't log, so it was worth the extra $150 to me.