If it's a Pierburg/DVG CDSU175 it could be the needle/jet that's at fault. Check the dashpot has sufficient il in it (sewing machine oil or ATF) and, if it hasn't then top it up and see if that makes a difference.
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loki_the_glt - Skipper of the Exxon Valdez, driver of Sweden's finest sporting saloon - and pining for another Slant-4.
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