So how do I improve fuel efficiency with aftermarket parts and maintenance?

I'm going to the mechanic soon. So I was wondering what I should tell him to check or replace. Oh and what kind of aftermarket parts should I look into?

I drive a 4 cylinder 2005 Nissan Altima 2.5S.

There is a ton of things that can impact your mpg...

Spark plugs & wires, timing, fuel pump, fuel filter, air filter, how often you change your oil, tires, shocks/struts, air pressure, proper alignment, etc...

The list goes on and on. Stick to your manufactures recommended maintenance schedule and you will be fine.

I don't know much about aftermarket effects on cars MPG so I cant comment on that.

intake and exhaust can improve fuel efficiencey, but it all depends on how you drive. gettin on the gas all the time is one of the worst things.

Correct,most people dont see good gas after they add intake,header and exhaust because they get a lead foot...although you should see better gas mileage after those basic mods.

Thread-starter,the best all around Altima board is will have all the info you need on mods and mtce for the car.

I just copped the K&N air filter for my 03 Altima SL.....my MPG improved a lot........so I would invest in that filter

my works at Mr Tire and did some other minor things for like add air to the tires, replaced the coolant, oil change and that also helped out my MPG