Hi,
My check engine light is on with a code 505 ( idle control system malfunction). It has been on before. If I reset the code the light goes off for 7 days of driving, then comes back on again with the same old 505 code. Why would it take 7 days to come back on ?
I am thinking of cleaning the IAC valve, sincee the car stalls with the a/c on at idle. But why would it take 7 days for the code to show up again ??
Thanks