timing belt / car whont start.
 

hey my car start overhiting. i took it to Audi diler. they told me the termostat and the waterpump are not working. so i changed them but since i took the cramshaft(timing belt?) out my car just keeps kranking but not starting. i checked everything and i found out that my sparkplugs dont get a spark??? any ideea what it can be???? thanx any info it will really help me. thanx a lot. p.s i have been told that there is a crank sensor. is there one??? thanx a lot.