Dale,
Most throttle response problems come from the TPS(throttle position sensor). without a reference to throttle position, your computer will not deliver fuel. Your engine will start and idle because the air flow is controlled by the idle air control(IAC) which bypasses air around the throttle plate during idle. Or as stated, maybe gas pedal sensor on the fritz. Hard to tell without the code. Best I can do for ya sitting here.
I would invest in a cheap code reader(around $40) and get the code for the check engine light(some readers erase codes). These new vehicles have sensors that go out left and right. The light maybe out but the code maybe locked in memory for troubleshooting. Most sensors are an electrical connector and 1 or 2 bolts. A chilton manual and code reader can save yourself alot of money in simple sensor replacements. For example, my wife had problems with our grandcherokee 2 months back. it was not shifting correctly and could not go over 35 mph. I plugged in the code reader(under driver side dash on all vehicles 1996 and later-obd2 plug) and got the code for an output sensor. replaced the output sensor(side of tranny-1 bolt and connector) for $49. good as new. I checked the local tranny shop. it would have cost me $250 for toubleshooting and sensor replacement. it took me 15 min.