My 89 XR7 5speed idles at 3000rpm all the time. It just started doing it one for no reason. I replaced the IAC because my car made the goose honk when i shut it off, but it made no difference. I have also checked for vaccum leaks all around. It still runs great and had lost of boost but when it's not making boost there is a whistling noise. I took my car to a shop and put it on the scanner and came up with these codes 82, 13, 26, 12. Can anyone tell me something else to try?