First, try using a short description in the title and putting the rest of your question in the post itself
Second, what "tune up" are you due for? Cap, rotor, points, wires, plugs? I hope you realize that the old concept of a "tune up" isn't needed on modern cars. There are no more distributors that need caps, rotors or points. And there aren't even wires on most engines because of direct coil on plug setups. And modern spark plugs easily last 90,000-100,000 miles before needing to be replaced.
I hope that's sarcasm.
If not, I need to go adjust the cable operated drum brakes, replace the cap, rotor, points and condenser on the distributor and adjust the mixture on the carburetor in my Veloster. I better check the air pressure in my bias-ply tires too.
Chances are you have a loose or worn connection... somewhere... It's going to be tough to isolate the problem. Possibly expensive too. I would start with the locking mechanism in the driver side door and work from there. But no guarantee that's even close to the issue.