My TPS will not ready 0% once the engine is running. With key on and the engine not running it will read 0 but once I start the engine it reads around 2-4%. Sometimes it will read around zero and the car idles good then but when it is around 2-4% the idle surges a lot. It kinda seems like possibly a ground issue but I'm not sure. This is on a 2000 Camaro.