Yep, that's your problem alright. There should be a vacuum line diagram on the core support on the driver side. You will need to get all those vacuum lines sorted out and you may even have to replace a vacuum switch or two under that plastic cover.

This whole contraption emulates the vacuum signal made by a gas engine. This will not be too expensive to fix unless the diaphragm on the back of the IP is bad. It is very expensive.

Good luck and Merry Christmas,