I have a 1990 legacy sedan with 175,000 miles on it. A few months ago
the check engine light started to come on after the car had been driven
for at least 10 minutes, then had been stopped and restarted. But,
after a sufficient amount of down time, about 6 hours, the light would
be off when i went to drive again. Since yesterday, the light has been
on continously. The car runs relatively well, it is a little rough at
starting and when I shut it off it just seems like the car is giving
up. The engine runs slightly labored, but that is no different from
when the light is off. It seems to be a product of the car's age. Does
anyone have any idea why this light is now on and seems not to be
giving up?