I replaced the gas tank cap and reset the error by disconnecting the battery. The code came back. Is the battery disconnect a valid reset of the code?

Thanks,
Dan

 

When you disconnect the battery, I think you have to keep it disconnected for a good 30 minutes so the memory retention in the PCM will be cleared.

 

I've reset my codes in a matter of 30 seconds when I've gotten them by disconnecting the battery so I don't think that's the case. If you want you can try cycling the key a few times with the cable disconnected and it will drain any power out of the PCM that it may be holding onto.