I am pleased to announce that my vehicle has passed emissions and will be good for two more years. Most of you are familiar with the beast after whom this blog is styled, and most are also familiar with the somewhat stringent guidelines the EPA has enforced on the area where I live, and so are therefore familiar with why I would be exuberant about such news.
Though I have done so
before to a limited extent, I thought I would share with you some of the things that help lower emissions. Some of these are from the EPA, who actually have a goodly amount of helpful information on their website, and others from various sources.
1. Make sure your engine is hot when it is inspected. This is probably the single most helpful thing you can do. It will cut some of your numbers in half. A warm engine pushes warmed fuel into the cylinders, and requiring less fuel and promoting more complete combustion. About twenty minutes of road driving is enough for most cars; however (as I understand it, and I could be wrong), mere idling is not as helpful as road driving, since it does not distribute temperature as well.
2. Cooler days are better for getting inspected. This is for two reasons: before the EPA started regulating such things, one of the major sources of emissions was not from the tailpipe, but evaporative emissions from the gas tank, the engine, etc. With the new control systems for such things, those emissions are more likely to show up in your tailpipe as higher CO, NO, hydrocarbons, or something else you are tested for in your area. Additionally, cooler air is denser, meaning that when "thin" hot fuel and "thick" cool air flow together, you get a higher percent of "clean air" coming out of the tailpipe.
3. A clean engine has less resistance and needs less fuel to do the same work. Keeping your fluids clean is helpful. For example, an oil change a few days before the inspection is helpful. Transmissions are closed systems and the newness of the fluid there shouldn't be a factor, but if you haven't done anything for it recently, there may be metal shavings slowing things down (probably not a big factor, but something to think about). Also, there are a lot of deposits that build up inside your engine that can be flushed out with gas additives such as
fuel injector cleaner, and my personal favorite, BG Products' pricey but effective
44k Power Enhancer.
4. Ethanol burns more cleanly than gasoline. You can use a mixture of 10% ethanol, 90% gasoline (probably more, but not much more) in a gasoline engine without any adjustments. Some old cars can be tuned to take a whole lot more, but you have to be good with timing chains and mixture screws. Since 1986 (I think), engine blocks have been sealed, so you can't play with the mixture, and you need new computer control chips to use a higher percent ethanol. However, a number of new cars and trucks (particularly larger American vehicles) are now available with computers that adapt to either gas or E85 (85% ethanol). Areas that have stringent emissions restrictions also often stock E10 gasoline. Otherwise, you can get ethanol at
these stations and make your own mixture. (Or you can get it from a moonshiner, but that has both quality and legality risks.)
5. As a last resort, you can replace factory products such as the catalytic converter, with more effective custom models. Your auto parts store will be able to provide you with better details than I can, and can tailor it to your problem (e.g., if you are only having trouble with your NO levels, maybe it is your EGR valve, not some other more expensive part).
The above may not be a learned treatise, and I am happy to accept corrections (especially from Motokeb), but that is what I have picked up over the last few years.
