P0505 The Comprehensive Guide to Idle Air Control System Troubleshooting

I own a 2001 Cherokee Sport. Recently I've been having an issue with my RPM at idle. It surges anywhere from as low as 300 RPM to as high as 1400 RPM. My check engine light is on and it's throwing the P0505 code out which is an "Idle Air Control Malfunction." I thought for sure by changing out the IAC sensor, ... OBD Code P0505 - Idle Air Control System Malfunction ... P0505 is an OBD-II generic code in which the engine control module (ECM) finds out the engine idle ... The error seems to happen before the Jeep ever starts, or the code does not get logged until the jeep is turned off. P0505 can be caused by not only a bad IACV but also a vacuum leak, misadjusted idle speed, bad ECT sensor/circuit, or bad TPS sensor/circuit. The ECM operates only the IAC valve to perform idle–up and provide feedback for the target idling speed. DTC No. DTC Detecting Condition. Trouble Area. P0505. P0505 is thrown when your idle air PWM cannot reach the desired RPM the ECU wants. I get this when controlling my idle with an aftermarket ECU ... P0505 Is a malfunction in the Idle Air Control system. The IAC valve is probably sticking. Only you can determine if you have the ability to do ... The error code you received is for a faulty IAC valve but it probably is related to the idle speed that you fiddled with.... The ECM regulates ... By description that code (P0505) is an idle speed contol circuit code for a N/A. ... Battery voltage is 10 volts or more. Ignition switch is on.