Battery cover thingy? You mean like a new battery post terminal? So it was a bad connection?
That's IT! Yep, he said that it was the post terminal, the connection wasn't good and it was falling apart. I parked the car at home and then turned it back on and it was ok but now, I gotta buy the part and see if MrPL has all the tools to replace it, otherwise, I'll be charged $100 for a 10 minute or so job.