I have a 2015 Acura with 81000 miles. It sometimes cranks strong and starts immediately. Sometimes it cranks weak and then starts. In two occasions it didn’t start but jump started easily. I took it to Autozone and they tested the alternator and battery and both were fine. I took it to my mechanic and he said they were fine as well. I purchased a small jumpstart kit just in case. Any advice? I know the starter could be the issue but my mechanic doesn’t think so.