I have the same problem every now and again...very infrequent. I think it has something to do with the car's security system- the computerized electronic key and the car computer recognizing the key. 9 times out of 10 if I turn off the key, remove it from the ignition, then reinsert it, it starts fine the second time. Always 100% by the third try. I wouldn't waste your time or money trying to track this down unless this happens on a VERY regular- even daily basis.

J.G.