The mixture adjustment is between the fuel distributor & the air flow plate just like the 16V. However you must remove a screw to access the 3MM allen that adjusts the mixture! AS you change the mixture you must cover that access hole with a "finger"(or re-install the screw) to block off a vacuum leak!

Timing for a USA car should be TDC(with vacuum) at idle & at 3500RPM between 32-35deg.

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