Il Thu, 06 Oct 2011 14:07:08 -0700, snipped-for-privacy@optonline.net ha scritto:
--------- Here in the USA many states don't measure emissions at inspection directly. They just use the information from the cars computer that shows the systems are working.
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Well, here in Italy we only measure the final result (i.e. emissions are controlled, no electronic is connected to the car).
And for euro 2 it might happen that you are being checked in a "not favorable" moment (if I can express myself in this way). Since you are asked to maintain the car with emission levels comparable to those declared when it was coming out of the factory (and not better...), you only need to drive it for a while, to obtain a (possibly, if nothing is really wrong) correct emission level. As a matter of fact, Euro 2 standard only measures emissions with engine in "standard working conditions" (the original standard was based on levels measured in controlled conditions, with tests run in engine test room).
I own a euro2 VW (Polo, gasoline, converted to LPG) of the same age of the ML320 of the OP and this happened to me at the time of the second check (2005). Simply driving it 5 km on the high speed ring around the town was enough to obtain a substantial reduction of emissions. After LPG conversion, I know I need to drive for a few kilometers using gasoline, in order to obtain a correct measurement: it's a sort of "reactivation" of the catalyzator. If I just drive to the test station running LPG and switch to gasoline there, for testing, the result is that the catalysator is running poorly and emissions are too high. It's a fact, but don't ask me why... :)
Of course, this doesn't mean anything at all, for the USA! :) It's just for... well, general information? :D