That's the gist of it. I've been taking my S2000 to a nearby dealer for annual scheduled service. Until recently, it hasn't needed anything more than that, oil changes, and tires.
Short version: Paid dealership to diagnose a CEL misfire issue. They misdiagnosed the issue. I did the work. I don't think they did anything wrong, but that they were lazy and half-assed the job wanting me to spend money before eliminating other likely causes, which I tested and found. They want me to spend money for diagnostic again. I think they should at least credit me for the half-assed diagnosis they did, and preferably also the cost of parts I used to make the repairs. That's only $60-$160 on what will almost certainly be a $1000+ service. But if they can't recognize they missed something simple, is that worth walking to another shop?
Longer Version: I started having a CEL misfire issue on my S2000 that I was at a loss to diagnose myself. Ended up punting the diagnosis to the local Honda dealer that I've been taking my S2000 to for regular service. They charged $60 to do the diagnostic that would be refunded if I used them for service. They pulled the new spark plugs I'd put in to hopefully fix the issue, and told me the problem was that I used non-OEM plugs. They were good, Bosch iridium plugs, but not OEM. They wanted to charge like $200 to replace the plugs... which they didn't even have in stock. I picked up my car and took care of it. Didn't solve the problem.
Fast forward. After finding a bad fuel injector, I finally did a compression test and discovered half compression on Cyl 4. berkeley. This is a bigger issue.
It's also something that, if they already had the spark plugs out to see that they were non-OEM, they could have just hooked up a compression tester right then to rule out the possibility of compression issues (which can easily cause misfires). They didn't do that, but just stopped at the first possible culprit before telling me to spend money.
Now, I want a shop to take care of this compression issue. I call them again, and they want me to pay $90 for them to more closely diagnose the issue. I think they should comp me for that. At the least, I would expect them to offer to comp the $60 I already paid.
It's not a huge deal, but... it really seems to me like they half-assed the job I paid them to do. Because they half-assed it, I spent unnecessary money and wasted a lot of time. They made a simple, completely understandable mistake. If they're not willing to own up to making a simple mistake and be willing to work with me after I've been a loyal customer, should I just tell them, "You're not the only game in town. I'm going to take my business to someone who strikes me as caring more about being diligent."?