If it's affecting the way something works, yes. IMO a computer diagnostic is some of the best money you can spend if it saves you a lot of diagnostic part-changing. If a shop tells you what's wrong you can still fix yourself. Before i had much experience i had 76 volare that I changed many, many parts on. I had old dist cap that I used. Still no good. Took to shop. Mech calls and says dist cap, $60. I said go ahead. Figured he'd see his error. he called again and said needs timing adjusted, $60. To turn dist? I told him he was done, grabbed my timing light and went. Paid him. Started car. Knew I was right. Adjusted timing. Ran like a dream. Best $100 I ever spent.