i would think you will need to replace the iac..from what you are saying here
DTC P0505: Malfunction in Idle Control SystemNOTE: If DTC P1519 is stored at same time as DTC P0505, troubleshooting DTC P1519 first, then recheck for DTC P0505. 1. Start the engine. Hold the engine at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on, then let it idle. 2. Check the engine speed at idle with no-load conditions: headlights, blower fan, rear defogger, radiator fan, and air conditioner are not operating. Is it 700 ± 50 rpm? YES-Intermittent failure, system is OK at this time. NO-If the idle speed is less than 650 rpm, go to step 3; if it's 750 rpm or higher, go to step 4. 3. Disconnect the 3P connector from the IAC valve. Dose the engine speed increase or fluctuate? YES-Adjust the (base) idle speed. If it's impossible, clean the ports in the throttle body. NO-Replace the IAC valve. 4. Turn the ignition switch OFF. 5. Remove the intake air duct from the throttle body. 6. Start the engine and let it idle.
7. Put your finger on the lower port (A) in the throttle body. Does the engine speed drop? YES-Adjust the idle speed. If it's impossible, replace the IAC valve. NO-Check for vacuum leaks, make sure the throttle valve is completely closed, and repair as necessary.
Is there any other way to test the unit before I replace it? If it wasn't a +/- $200 part I wouldn't hesitate. Let's just say I would be disappointed to spend the money on the part, spend the 60-90 minutes replacing it, only to have the same P0505 code come up. This is an issue b/c I can't register my car without passing smog (test only station), and I can't pass smog with a check engine light on. Thanks Tim. --CapnBarry
i can understand that
but,,these are the only test i have
give me one moment
i will check something else
thats all i have
be sure the vaive is clean...sometimes cleaning the iac will fix this
check the wire harness and the plug to the iac
but,,you may end up buying the iac
A final clarifying question. If I took the car to some mechanics, would they use exactly the same tests? OR, would they have additional test/diagnostic equipment that can plug directly in to the IAC to test its functionality? It could be worth the committed 1-hour at $75/hr, just in case it is not the part and could be addressed via adjusting the throttle.
sorry i was off line
i would think they would use these tests
although the right diagnostic scanner may give additional information