Q: Car slow to accelerate when in drive

It appears from the description that there are multiple issues going on with your Cadillac Catera. A blown head gasket will definitely cause both acceleration issues and white smoke emitting from your tailpipe. Before we can address the possible transmission issues, the blown head gasket needs to be addressed first in order to move forward. This will verify if all of your car’s symptoms trace back to a blown head gasket or if they fall somewhere else. It may be time to enlist the assistance of a certified mechanic to come by and inspect your Cadillac and confirm if your head gaskets are blown or if the slow acceleration problem lies elsewhere. They will be able to assist you in making the necessary repairs needed to get your engine running healthy and determine if your symptoms have been resolved or if further diagnostic work is required.