Check Engine Light!!!

[U2_slow]

Yeah so my CEL came on and I checked the code, it came up as P0505 - "Idle Air Malfunction," so I took apart and cleaned the throttle body, as recommended, replaced the Idle Air Control Valve, like my mechanic told me, and checked the vacuum hoses...

I reset engine ECU, the same code popped back up... the car idles perfectly now, but I have to do smog and the car automatically fails if the CEL is on, any advice on what to do now would be greatly appreciated.

 

[ClevelandDSM]

Like said before, trace your wiring and make sure that you have no cracks or small tags. Also go over your vacuum lines " lightly " with something like wd40\pbblaster\ or starter fluid. remember, Lightly. Put a little around your throttle body also. If the car revs up some, you know you have a vacuum leak.

 

[eeeewidner]

1. Check the Idle Air Control (IAC) steps with a scan tool. With the engine fully warmed up at idle, the steps should be between 2 and 20. If the steps cannot be viewed with the scan tool, and the idle speed is too high, the motor can be run manually to see if the RPM will come down.

2. Unplug the IAC motor and locate the pins on the motor that correspond with the Green/Red wire and the Green/Black wire. Using two jumper wires, apply 9 volts (from a 9 volt battery) to one terminal and ground to the other, the motor should move one direction and should affect the RPM. Reverse the jumper wires and the motor should move in the opposite direction.
Make sure it can raise and lower the RPM. If it doesn't, the motor is bad.

Vacuum leaks will not throw this code on most DSM's unless there are multiple problems.

 

[Project2G]

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