2001 Dodge Dakota Truck stalling at stop and bucking while

Truck had a vapor issue which was fixed after shop fogged it and replaced the TPS. Now the truck is stalling when it is stopped. When we drive it bucks as if it wants to stall. Shop said it could be the computer resetting itself but did not see any error codes. They cannot find resolve the issue. What could it be? Is the new TPS either bad or installed worng? As a note we ran higher octane gas and used Seafoam to clean the fuel system when it first started. Did not hurt or fix the issues. Problem persists when tank is full all the way down to 1/4. There does not seem to be any electrical issues.