I had the A/C fixed in the van, they replaced the evaperator, and now there is a hissing sound upon acceleration. At first I thought it may be a door trying to close due to a vaccuum leak but I couldnt find anything. It sounds like its coming right out of the black box under the dash where the evap is. It is really loud and only does it when your giving it gas. Once you let off the gas it stops. Any ideas?

 

low freon new minivans dont use vac lines. What year van?

 

The van is a 98 T&C. The A/C works fine. It was fixed about 3 months ago. I just got back from South Carolina. 100+ heat index. No problems staying cool. Could it not have gotten vacuumed down all the way?