Well, First Lets Answer A Few Questions.Does The Truck Have Good Fresh Gas??Is Your 302 A Fresh Rebuild??Is Your Vacuum Advance Plugged When You Time It??What Are You Setting The Timming At?? And To Answer Your Question On The Ping.You Must First Answer These Questions.If You Answer YES On All The Above The Answer Is Yes It To Far Advanced.10-4 GMCJOHN


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