This is a very interesting question and one that is significant to many older Mercs since many models have been tagged as "high emitter profile" by the CA Bureau of Automotive Repair (BAR), the state agency that oversees emission testing.

Since 1973 new cars have been certified to what are known as "absolute standards". The certification test lasts about 45 minutes, including an engine off hot soak, and the entire exhaust from the full test is collected in a big plastic bag. The collected exhaust gas is then sampled for proportional emissions and combined with the total volume to arrive at an "absolute" grams per mile value for HC, CO, and NOx.

The way this works is that a light car can be relatively "dirtier" than a heavy car, since the lighter car produces less total exhaust gas volume during the test because less fuel is required to drive the entire test cycle.

The CA Acceleration Mode Simulation (ASM) loaded dynomometer test measures proportional emissions in PPM or percent, and the "cutpoints" calculation includes the vehicle weight, so heavier vehicles have slightly lower cutpoints than ligher vehicles.

Nevertheless, it is arguable that a car above the cutpoints, especially if it only marginally fails, would not necessarily fail the full certification test. The cutpoints are arrived at via statistical analysis, but are not perfectly correlatable to the absolute certification limits.

"Conditioning" is also an issue. In the case of many KE equipped engines, converter temperature is an issue. If they are shut down or idled too long before the test is run they can fail because the converter cools off.

This is the kind of thread where anyone can vent their frustation, and that is a good thing to do, but the important point is that every CA resident should contact their state senator and ask the question I posed at the top of the thread and keep after them until you get an answer.

Unfortunately, car guys are all too willing to say F-it and walk away. If more would take active part in the political process this kind of ridiculous legislation would be less common.

I have a three page MS Word document - "The war Plan" - that I will e-mail to anyone who wants to help, but I don't think I've heard from anyone on this board.

dukewilliams at netzero dot net