I have a 1988 Chevy S-10 Blazer. it first started out by "bucking" on acceleration, and only when warm. i really didn't think much of it.then it died. my first thought was fuel pump, so repaced it. would not start until you held your foot on the gas pedal. but whne you tried giving it gas it would die and not start again. so someone said the timing. checked, had too much play in chain, replaced, timed, changed wires and plugs. still no start. checked rotor, no cracks. the jets are spraying fine, and is not flooded. i am learning about mechanics, so i am lost on what to check next. an help will be appreciated. thank you in advance.