My 03 Mitsubishi Eclipse GT will go about 2 weeks being quiet and then out of nowhere upon startup (usually on cold days) will make a lawn mower sound. But the other day it was -6 and didn't do it so I'm not sure why. I tried changing the oil to synthetic thinking there could be engine sludge making the oil not circulate to the top of the engine and that seemed to work for a while but it just started again. Sounds like the lifters but it only does it sometimes so it has to be the oil right?

 

motorgremlins.
Evil little bastards. Dont fuel up after midnight and dont get them wet.