Throttle Position Sensor Malfunction (P0505) The Ultimate Troubleshooting and Repair Guide

The error seems to happen before the Jeep ever starts, or the code does not get logged until the jeep is turned off. 2004 Toyota Matrix XR with only 111000 miles. You made multiple changes to the motor that all change the cylnder fill rate. That would require a new map. The code might be from an IAC issue ... The code P0505 - Idle Control System Malfunction means that the engine computer cannot regulate the idle speed. In other words, the actual idle speed varies ... The P0505 code means there is a short in the IAC valve circuit. I replaced the valve, check the wiring and old valve - both where ok. I'm ... So over a month i had a CEL, which was the idle air control valve, i replaced it the IACV with an excellent one. Its still reading P0505, ... 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 ... This code happens when the actual idle speed varies from the target idling speed by more than 200 rpm, for five times or more during a drive cycle. Celica Forums General Discussion General Code: P0505 ; IDLE AIR CONTROL SYSTEM FAULT. It sounds like you are going to need to replace the Idle Air Control Valve. The IAC Valve is mounted to the side of the throttle body.