A car repair facility did an unauthorized repair

(tolld ok for a fuel pump by texting did an oil pump instead but on top of the error it did not fix vehicle) then charged after the fact for a teardown $500. Upon learning the wrong repair, and in the tear down the real problem (it was what I told him going in). Repair guy told he would be paid for the authorized job which was the teardown only and I was picking up vehicle. He refuses to put vehicle back together, he refuses to allow me to see my vehicle, he refused the insurance company to see, BAR has gone in but cannot make him release the vehicle. I am going to small claims court. How do I sue him for maliciously keeping me from my vehicle. This has dragged on for 7 months, I have had to rent a car, pay payments on the vehicle, insurance, on star and has added horrible havoc to my life. I have documented by text the repair was a fuel pump, I have documented my expenses that I have paid out, I have documented my several attempts to get the car back and today I am giving him a demand letter for all my damages but I want to do it right. Regards, Debbie