So I purchased my 03 g35 sedan a little over a month ago and everything runs amazing but two weeks ago my check engine light came on, so I took it to this mechanic I know and the code P0507 came up with "idle air control system, rpm higher than expected"... so he reset it for me and told me to use "sea foam" the next time I fill up gas(I use premium), and he said that should fix it, but the check engine light came back on, so I'm asking if anyone has an idea of what it could be? The guy I know says it may need to be cleaned or it may be a bigger problem but he didn't say what, so if anyone could tell me what it may be that would be great.

 

http://www.nicoclub.com/manuals/G35/...5_Sedan/ec.pdf

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