PO507 code higher than expected idle

My Grandmother yes 81 yrs old grandmother has a 99 Camaro convertable. Still like new condition.. She gets an engine light and when I pull the code I get the 507 code. I inspected everything i could and still can not find the problem.. What causes this and were can i find it.. I want to find the sensor that triggers this. Now the idle does surge when light comes on but then drops to normal. I really work on more Fords and I never ran into this code before. Of course on the Ford I do run into about every code you can think of. LOL Please help me help grandma.. This Camaro has the V6 not 8. I have done other work to it but this ones got be beat.. Thanks,Gary

Still looking for this problem. Still coming up with nothing.. Any one.. Thanks,Gary

Here is some info I found fairly quickly. The first link will show you all DTC codes for a 1999 Camaro.
Second link is specifically for po507. Hope this helps!!

http://gearchatter.com/viewforum35.php?sid=171326498721f63d8b7cf83caaf088 d2

http://gearchatter.com/viewtopic8841.php?sid=171326498721f63d8b7cf83caaf0 88d2

Thanks a great deal for the info.. I know a lot about the IAC and emissions systems.. I do suspect that.. Just trying to narrow things down.. I see its not as common on the Camaro as it is on a V6 Buick with similar engine.. I guess that like my grandmother they don't get down on the throttle on a Buick like you would in a Camaro. A heaver foot sometimes keeps the carbon down. :grinyes: When I looked in a same year model Buick with the similar engine it pointed towards the IAC and emission. So thanks a great deal for the info and I will post back my findings.. The car was very well serviced. Still looks brand new Convert-top and all.. SO I will go try to make my grandmother happy.Right now the light is still off after a week.. I put my Cpu to it and everything checks out ok.. Thanks again,Gary