Hey Jake, glad to hear your problem didn't leave you stuck anywhere. I didn't get your message until late last night and totally spaced calling you back today.
Sorry 'bout that!
I don't know that you'd have a loose connection in the main harness, since your car is basically unmolested. Those harnesses don't just come loose on their own. But a specific sensor failing might be the culprit. I thought there was a specific code for TPS issues though, so getting a general error like you got seems odd if it's the TPS. If it's intermittent, really all you can do is wait for it to happen again and hope you can notice a pattern to how you were driving or something when it occured.