I just did an oil change on my 1995 Nissan Altima, and noticed that the gasket on my dipstick does not make a seal inside the dipstick tube. The inside diameter of the tube is maybe 3/32 of an inch larger than the dipstick gasket. I don't know if this is how the car came or if this is an aftermarket dipstick. The gasket is made of rubber and appears to be in good condition. It's been this way for at least 6,000 miles, as that's when I last had the oil changed. Though, for all I know, it could have been this way for all of its 145,000 miles.
It's a 20 year old car and, accordingly, it has some issues. The idle occasionally fluctuates, and the exhaust smells a little rich. Overall, though, it runs good. Is the non-sealing dipstick a big problem? Should I expect significant improvement or extended engine life if I manage to find a good replacement?