Something in the enrichment circuit. On my '85 the warm-up regulator changes the control pressure when there is a drop in engine vacuum (ie. stepping on the gas). Not sure if your '92 is similar, just throwing it out there.

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma