I have a 97 cad deville that i have replaced the fuel pump and the filter, im getting fuel, but no start .. problem began when i let it sit for two months, found i had a weak battery, charged it up put it back in and no start .. so i changed out the pump, crankshaft position sensor and still nothing ..am i missing something ? Right now its only showing c1210 as a current code which is only the brake switch..

Do you have spark?
Try un plugging the MAF sensor and see if it will start...

Need to check to see if your getting fuel into the cylinders.

I would get that battery checked before spending time or money on anything else.