I have a 1997 ford f150 4.2 V6 2WD. Could somebody please tell me where the egr valve is and how to clean it. I tried cleaning the IAC to help with my crappy idle but it didn't do much. thanks.

 

Thats not your idle problem most likely , but it's up front on the V6, to the right of the alternator .

Clean your throttle body and MAF sensor - you need a clean air filter and take your IAC back off and work the Mechanicals inside with a small pair of needle nose pliers to free them up so they work (that's prolly the prob) - you can use WD 40 . You should do the other things mentioned..