My Kingdom for a NOx Sensor

[cfg83]

Hello -

First a little background. In August I passed my emissions test :



My car passed with great numbers for HC and CO pollution (below the average !), but the NOx was higher than normal. I did have the HAI (Hot Air Intake) online, so maybe this is an effect of the (mild) lean-burn :



I didn't have the ScanGauge online, but I would guess at least 130+ degrees F HAI.

I also have an EFIE from Eagle Research (Eagle-Research:) that adds a voltage to the 02 sensor. This will also increase my lean burn and therefore my NOx.

Today I was posting in this thread ...

what do you think of hydrogen mods (with video)
what do you think of hydrogen mods (with video) - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com

... and Lazurus pointed out my ethical dilemma :

Originally Posted by Lazarus

Have you had any reports on the emissions that is created when running lean? I wonder if the Nox goes through the roof or does the hydrogen do something to counteract that?

Now, here's my problem. I want to increase MPG and stay within my car's stated legal NOx limits. Because of this is I want to monitor my NOx in real-time. That makes "normal" smog station NOx sensor setups out of the question. Soooooooo, I have been roaming the net. Up to now I have only been able to find this :

Smart NOx Sensor
VDO - Smart NOx Sensor


The good part is that it is obviously designed for a car's harsh environment (it looks just like an oxygen sensor!). The bad part is that it doesn't seem to be for sale (yet), delivers a digital signal (a voltage is all I want), and probably costs an arm and a leg.

VDO engineered this sensor with NGK, and here is what they have to offer :

(NGK) Sensor Technology
NGK Automotive Ceramics U.S.A., Inc.


I like the NGK NOx sensor more because it seems to be offered in a non-smart (voltage only?) version.


Question : Does anyone know of NOx sensors for gasoline and/or diesel cars that are in the sub $100 range?


URL Appendix .......................................

Here are some other close-but-no-cigar leftover URLs from my googling :

New Sensor-Based Diesel Emissions Control System
Green Car Congress: New Sensor-Based Diesel Emissions Control System

Before IMITEC there was no NOx sensor for diesel engines, though such sensors do exist for gasoline engines. We essentially adapted that technology for diesel, so we can offer another option to engine manufacturers.

CO and NOx dual sensors (looks too flimsy for auto applications)
MiCS

MiCS 4514
This sensor contains two dedicated gas sensing chips, one for reducing gases (CO/HC) and one for oxidizing gases (NOx). The two chips are fully independent.

High-sensitivity, rapid-response nanotechnology NOx sensor
High-sensitivity, rapid-response nanotechnology NOx sensor

Conventional NOx sensors do not have sufficient robustness or heat resistance in the harsh environment of engine exhaust gases. To solve this problem, a multi-chamber sensor that uses a solid oxide electrolyte (oxygen-ion conductor) has been developed. This, however, inherently does not give a high-speed response, because it has a rather complicated structure and it measures NOx concentrations by combining multistep electrochemical reactions. This poses a problem in relation to the purification of exhaust gases and reduction of fuel consumption.

Geneva Motor Show: VW Touareg BlueTDI
Geneva Motor Show: VW Touareg BlueTDI - egmCarTech

The Euro-4 standard currently specifies a NOx limit of 0.25 g/km here. The US standard, which the Touareg BlueTDI satisfies, specifies among other things a NOx limit of 0.043 g/km (0.07 g/mile).

Emission Control Technologies for Off-Road Diesel Equipment
Manufacturers of Emissions Control Technology || Off-Road Diesel Equipment

NOx Sensor: NOx sensors represent state of the art technology that can be applied to gasoline lean burn engines as part of a broader engine control or diagnostic system used to insure proper operation of the NOx emission control system. These sensors can be incorporated independent of the NOx emission control technology used on the vehicle and their function is primarily to monitor the NOx conversion efficiency of the catalyst.

Keeping watch on car emissions
Keeping watch on car emissions

It is also possible to use sensors that respond directly to concentrations of the pollutant gases e.g. NOx. While these are common in test benches and workshops, they are too expensive to be fitted routinely to cars.

Toyota's DPNR System: how engines, catalysts, fuels make clean-diesel
Toyota's DPNR System: how engines, catalysts, fuels make clean-diesel | Diesel Fuel News | Find Articles at BNET

An air/fuel ratio sensor, exhaust temp sensor, and pressure differential sensor regulate catalyst regeneration, rather than a NOx sensor -- a lesson that today's pricey NOx sensors perhaps could be avoided.

Cummins seeks better NOx sensor for closed-loop emissions control
Cummins seeks better NOx sensor for closed-loop emissions control | Diesel Fuel News | Find Articles at BNET

A cheap NOx sensor that is capable of detecting as little as 20 ppm of NOx in real time exhaust is needed to hit EPA's 0.2 grams/bhp-hr NOx limit for 2007-2010, especially for urea-SCR, Cummins said at SAE Congress (see SAE 2002-01-0287). Cross-sensitivity to ammonia (for urea-SCR) could further hamper the effectiveness of a NOx sensor, researcher Qingwen Song explains.

NOx OBD Application (more details on the NGK sensor)
NGK EUROPE

The NGK NOx sensor for reducing NOx tail pipe emission is a stand alone component, it means no further calibration is required. Easy system integration can be done by CAN-BUS.
It can also be used for On-Board Diagnosis (OBD).

Thick Film Zro2 Nox Sensor for the Measurement of Low Nox Concentration
Thick Film Zro2 Nox Sensor for the Measurement of Low Nox Concentration

Abstract:
A practical ZrO2 NOx sensor using dual oxygen pumping cells has been introduced for the control of NOx emitted from a lean-burn gasoline engine and diesel engine. However, the mea accuracy was not high enough to be useful for controlling or monitoring a low level of NOx concentration such as several tens ppm behind a three-way catalyst or lean NOx catalyst which is NOx adsorption or De-NOx catalyst.

CarloSW2

[SVOboy]

Damn, that's a terrific amount of links! I've never even heard of a nox sensor you could buy for your car, but my guess would be that they would be hard to get below 100$.

Ebay? Sales?

[cfg83]

SVOboy -

Originally Posted by SVOboy

Damn, that's a terrific amount of links! I've never even heard of a nox sensor you could buy for your car, but my guess would be that they would be hard to get below 100$.

Ebay? Sales?

My thinking is that they are "on the cusp" of large scale manufacture because of the increasing restrictions on EU diesel emissions. Orrrrrrrrr, maybe they already exist on certain trucks.

CarloSW2

[cfg83]

Hello -

I'm going to keep using this thread as a dumping ground for info I find (aka notus repositorius) :

Integrated Material and Information Technologies for Novel Emission Control Systems
http://www.imitec.org/

The project started in April 2001 and finished in June 2005.
The scope of the project was to develop an integrated sensor platform for next-generation emission control systems such as particulate (soot) filters and nitrogen oxide converters through systems integration of micro/nano materials technologies, virtual sensor simulation algorithms and instrumentation of emission control devices. This is in direct response not only to future market potential of these technologies but also to explicit statements of the EC to push sensor development for such applications by 2008. After incorporating software modules with the sensor elements the integrated device was tested under realistic conditions for developing modalities and strategies for feedback control of the system. Finally, LCA/technoeconomic assessment for the developed technologies was carried out

Development of a High-Sensitivity Rapid-Response NOX Sensor - July 4, 2007
Development of a High-Sensitivity Rapid-Response NOx Sensor

Conventional NOX sensors do not have sufficient robustness or heat resistance in the harsh environment of engine exhaust gases. To solve this problem, a multi-chamber sensor that uses a solid oxide electrolyte (oxygen-ion conductor) has been developed. This, however, inherently does not give a high-speed response, because it has a rather complicated structure and it measures NOX concentrations by combining multistep electrochemical reactions. This poses a problem in relation to the purification of exhaust gases and reduction of fuel consumption.

The newly developed sensor has extremely high selectivity toward NOX molecules as a result of precise control of the nanostructure of the sensing electrode that detects NOX. This structural improvement to the electrochemical cell gives the speed of response for the direct detection of NOX molecules that is five times as fast as that of a conventional sensor and the detection sensitivity that is doubled.
...
Strenuous efforts are being made to develop lean-burn technologies for gasoline-fueled vehicles to comply with societal demands for reducing CO2 emissions and better fuel consumption. However, although lean-burn engines produce less CO2 emissions, they produce more NOX emissions than conventional engines. Existing three-way catalysts cannot be used to eliminate NOX emissions under lean combustion because of the high concentration of oxygen in the exhaust gases. Instead of the three-way catalyst, a practical lean-burn engine uses a NOX storage–reduction catalyst system.A NOX trap material in this catalyst absorbs NOX during lean-burn condition. When the catalyst becomes saturated with NOX, a rich spike (excessive fuel supply) is generated in the engine, and this excessive amounts of fuel reduces and purifies the absorbed NOX.

ZFAS®-N2（NOx Sensor (under development)）
NGK SPARK PLUG CO., LTD. | ZFAS®-N2（NOx Sensor (under development)）

This sensor can simultaneously measure the NOx concentration and the oxygen concentration in the exhaust gas. It contributes to energy conservation and clean air through NOx control in gasoline DI engines and diesel engines.

CarloSW2

[DAN]

any lean burn motor make too much nox. ford tried to put a 30 to 1 lean burn in their taurus. they could not get the nox even close. the way they do nox is to cool the burn so the nitrogen in the air is heated less. for mpg and power a hot burn is needed. hydrogen can be used to fire a very lean mix. and that's a lean burn motor. water injection would cool the burn but would not met fed rules. and messing it up or down makes the engine check. light come on .in the latest op (whatever) 2 engine management.

[cfg83]

DAN -

Originally Posted by DAN

any lean burn motor make too much nox. ford tried to put a 30 to 1 lean burn in their taurus. they could not get the nox even close. the way they do nox is to cool the burn so the nitrogen in the air is heated less. for mpg and power a hot burn is needed. hydrogen can be used to fire a very lean mix. and that's a lean burn motor. water injection would cool the burn but would not met fed rules. and messing it up or down makes the engine check. light come on .in the latest op (whatever) 2 engine management.

You just tipped my hand, . My long term goal is to see if I can use a combination of a real-time NOx Sensor + EFIE + Hydrogen Generator to see if I can raise my MPG while maintaining legal NOx emissions. My goal is to be a lean, not so mean, clean emissions machine.

CarloSW2

[Wonderboy]

this sounds like a wise idea to me. i like itand i'll stay tuned.

[JohnnyGrey]

Please don't tell me you're using an EFIE on a narrowband sensor.

If you want to go lean, get a wideband with an analog 0-5v output.

If you're trying to reduce NOX, go with water injection. AFAIK, it's 50 state legal. I use it on two of my vehicles for performance reasons, but it's function is the same, to keep combustion temperatures down. I'm pushing 19 PSI on a 9.25:1 motor with 87 octane fuel. I'd say it works.

Pick up a shurflo agricultural pump, a brass M1 nozzle from McMaster Carr and the rest you should be able to pick up locally. I'm using an M5 on my Saab, but it only runs under tire shredding power levels.

[cfg83]

JohnnyGrey -

Originally Posted by JohnnyGrey

Please don't tell me you're using an EFIE on a narrowband sensor. ...

Yup, but it's offline because I can't justify the (likely bad) NOx :

http://ecomodder.com/forum/showthrea...efie-1308.html

Even with it off I've already drifted into bad NOx :

http://ecomodder.com/forum/showthrea...ison-6826.html

... If you want to go lean, get a wideband with an analog 0-5v output.

If you're trying to reduce NOX, go with water injection. AFAIK, it's 50 state legal. I use it on two of my vehicles for performance reasons, but it's function is the same, to keep combustion temperatures down. I'm pushing 19 PSI on a 9.25:1 motor with 87 octane fuel. I'd say it works.

Pick up a shurflo agricultural pump, a brass M1 nozzle from McMaster Carr and the rest you should be able to pick up locally. I'm using an M5 on my Saab, but it only runs under tire shredding power levels.

I'll research it. I do know that my co-worker had a water-injection system on his 1980's carbed truck. I *want* to say it was an Edelbrock, but I can't remember. When he took it for smogging in the 1980's, the tester said it was the cleanest vehicle he had ever seen.

CarloSW2

[Christ]

I can't chime on this, really... I've seen water injection, but only in use on HP vehicles, only a full throttle/boost, and only when the engine starts knocking. The injection cycle begins as a function of the ECU's inputs, rather than just relying on always on or driver-on.

I think MegaSquirt has a function for it.

The reason I actually posted here is because I still wonder about the NOx sensor thing... if anyone's done it, how to do it, and where to get the parts from?