I currently own a 2005 4.3L S10 blazer with 121700 miles. Just popped a check engine code and it showed that it was running too lean. Didnt even think to look at which specific code for it was, which i should have, but oh well.

Ive replaced the mass air flow sensor at 85000, and the spark plugs and air filter have both been replaced within the past 20k miles. So i am just curious as for what else to look at. Id hate to replace the spark plugs again, because anybody who owns this particular model blazer knows how much of a complete pain in the a$$ it is to replace them.

Any guidence? Thanks!