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> CRUISE HC/ppm=0083 limit=0900 CO%=00.73 limit=06.00 CO+CO2%=13.58 > IDLE HC/ppm=1185 limit=0900 CO%=00.16 limit=06.00 CO+CO2%=07.51 > > I passed all but the HC @ idle. The test allows up to 1100 rpm idle speed > during the test. The last results shown above, the idle was at 651rpm. High HC is a symptom of incomplete burning of the mixture. If the mixture is too weak (which it seems as 3% CO is about right for these carbs) it may not be burning properly. Also, too low an idle will tend to aggravate poor firing, as also will ignition problems. Valves needing adjustment (also poor valve seating and compression), a clogged air-filter and crank-case ventilation problems can also contribute to high HC levels. Try unscrewing the mixture screws a tad (maybe up to 1/8 turn), and check again. If that makes the idle speed also rise a bit, that would help (and prove it was too weak). It seems odd to be so bothered about emissions, but allow a pass if you've spent some money in a shop! Almost like an official bribe. Dave. UK VW Type 3&4 Club http://www.hallvw.clara.net/ ------------------------------------------------------------------- List info at http://www.vwtype3.org/list or mailto:help@vwtype3.org