There are connections from the PCM to the EATC module which are likely related to your issue. The problem is there isn't any information as to what to expect and the user manual (96 in my case) doesn't mention any relationship between acceleration and fan control. It actaully doesn't make sense. QUOTE]
The purpose of the vacuum cannister (reservoir) is to provide a 'storehouse' of vacuum when the car is under acceleration to keep the dampers in place. There is a check valve involved. Losing air flow when accelerating points to the reservoir as the problem. Common problems associated with the cannister are a broken line or the cannister itself fills up with water (condensate). Removal and shaking out solves the problem.