Ive searched through and cant seem to find the exact problem. Similar fixes wont resolve my issue. I have an 02 3.8 impala. Had a blown engine when i got it. I dropped a 3.8 from a 99 park ave into it. Has worked fine for about 9 months however the check engine and security lights stayed on. Today i cleared the CEL and now appear to have a security issue with the security light flashing and vehicle not starting. None of the relearn or bypass fixes seem to do anything. Hoping i dont have to tow it to a dealer. Any suggestions?