I need help in diagnosing a problem that I have with a 1999.5 a 4. I got the dtc codes but don;t know what they mean, the codes are 17953 and 17967.The car starts and idles but when you press down on the gas pedal the engine's rpms vary 1000 to1500 as if searching for the right place to be. I was told to replace the throttle body but that didn't help,any help would be greatly appreciated.