I had my car towed into a chain autoshop, they said it was the fuel pump for 600, after they finally found out at the end it was a broken ignition key, I guess with a security sensor they still charged me for the pump, any recourse?

Doesn’t hurt to ask.
A big discount at least because…unless they invest all the labor to take OUT the new fuel pump and put back IN your old one…you did get a new fuel pump in the long run.

myself, I would expect some compensation for the bad guess and extra down time though.

I agree with @kengreen. BTW…stay away from chain autoshops, chain oil change places and the like. Find a good, independent mechanic in your area.

I once had an independent mechanic misdiagnose a coolant leak. He thought it was a Welch plug (freeze plug) which could only be replaced by removing the transmission. He did remove the transmission to discover that the problem was a leaking heater core. He didn’t charge me for removing and replacing the transmission. I even tried to compensate him for his labor, but he wouldn’t hear of it.

@Triedaq that mechanic had great integrity