Occurred after failing to properly reconnect wires. Connections re-established, but warning lights persist. I tried to replace the spark plugs in my 02 camry xle v6. I gave up when seeing that the rear plugs are too far behind the intake manifold then is worth my effort, and decided I would just pay to have it done. When I reconnected all the wiring, My check engine light, VCS light, and Tracs Off light came on and my car was stuttering. I took a look and found 2 loose connections - one was the connection to the EGR valve and the other was a spark plug wire (I think).
After fixing the connection errors, the car stopped stuttering and everything seemed to be fine, but the warning lights were still on. I took the car to Autozone to diagnose the check engine light, and got error codes p1410 and p0304, which doesn't surprise me since one is an EGR valve position sensor circuit malfunction, and the other is a cylinder misfire on cylinder 4. I am wondering that since the connections have been re-established if I have anything to worry about and can just re-calibrate the check engine light and VCS and Tracs Off Lights