Pontiac Repair: no cam signal, cam sensor, sequential injection

Question
QUESTION: car was in for killing while driving wait a few minutes then would restart. now wont start scanner says no cam signal when cranking over so replaced cam sensor still nothing???

ANSWER: Model and year of car and engine size?


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QUESTION: Sorry.2000 pont grand am gt 3.4.

Answer
The Cam signal shouldn't matter If I'm correct on this. That is only used for misfire diagnostice and to put the engine into sequential injection. when it will not start what is it missing other then the cam signal? Does it have spark and injector pulse? How about fuel pressure tht enegine needs a minimum of 45 PSI to run decently.