my hyundai santa fe is slow starting. We have done all the usual. HELP

slow starting or slow cranking, as in engine turns freely and fast, or more of a dead battery slow crank sound?

John, Thanks for your help but its not the answer in my case . I will be more specific. We have changed and or replaced the following. Heater plugs. All seals with ref. to fuel. Replaced fuel filters. Sometimes it will just turn over and not start at all. The battery is in full charge state. With a tow it starts immediately. When driving along it has just cut out and stopped. Very embarassing for my wife who drives it. At present it eventually starts but is not responsivr to throttle. Could it be the crankcase sensor or is there something that we have missed. Any suggestions would be gratefully received.

it can be any and or many sensors. crank shaft sensor or cam sensor can do that have it checked for codes (those sensors will have random/many mis-fires). so please report back with any more info., still there is no direct answer.