<VV> Non-Corvair GMC Advise Sought

[Grant Young]

If anyone out there is/has experienced a similar problem with a late model GMC 5.3L engine, please drop me a private reply. This 2005 Yukon will sometimes shut off completely if the accelerator is pushed (such as to pass) at highway speeds. Then it coasts to a stop, sits for a moment, and then you can restart the engine and drive away as if nothing was wrong. It seems to be fine under easy acceleration. We have replaced the plug wires, plugs and fuel filter (which was pretty dirty) after 60K. Since then the problem has improved but still occurs intermittently under the same conditions. An Advance Autoparts hookup showed "multiple cylinder misfires", but the engine seems to run smoothly and there are no warning lights other than a check engine light which came on briefly during one of the stops. Help if you can! Thanks,
Grant Young