First thing I would do is a compression test on cylinders, then fuel pressure test. Make sure your starter relay is good. If it is cranking over but not firing could be fuel relay, fuel pump, and could be as simple as a vapor lock. Spray some starter fluid in the intake, if it fires up for a couple seconds, then tells you not getting fuel, and this narrows down the search to the fuel pump relay, fuel pump.
Now your statement is YOUR CAR wont start or idle, as you can tell that is two different things. Which one is it, wont start at all? or starts then dies because it wont idle?If it wont start, then check the things I just advised, if it wont idle, then that could be plugs,coils,idle arm, fuel filter possibly clogged. List goes on and on. Need to know little more detail of what exactly it is doing, and what you have already checked or tried for me to dissect it down more direct with trouble shooting. I can help you for sure, just little more info needed, or you can go through the list I just said and it will I am sure fix problem once you check and repair or replace as you come across that problem area that is not functioning proper. Thanks Mike
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