Hey my 04 at G coupe has been giving me horrible gas mileage. I was told to give it a tuneup so i changed the oil and spark plugs and air filter. its still running sluggish. is there anything else i should do??

 

It's a G35..... What's your MPG? 14-16mpg is normal.

 

How about the air filter?

 

You'll never get good gas mileage if your car is running sluggish. Take it into Nissan and have them find what's wrong, could be anything from a sensor, vacuum leak to spark plug wire....shouldn't be difficult to locate with the right tools. (you didn't mix up the plug wires when changing plugs?)
Gary

 

the plugs are correct and there isnt any check engine light at all. im gonna calculate the mpg soon. most of the times if something is wrong it would be a check engine light right?

 

I get between 15.5-16 MPG. I have never achieved anything higher than like a 16.5

 

i've gotten 26 mpg, but that was on the highway doing about 65 mph on properly inflated tires. Make sure you always use premium.

I was concerned myself when i saw some of my city/highway mpg. mine is around 16-17 mpg, and thats a mix between city and highway.

I see u also live in NY where it actually gets cold compared to some of the guys on this forum from SOCAL. i find my fuel economy on all my cars drops atleast 10% due to low temperatures.

Also, sometimes my car feels a bit sluggish, but it is because it ,is slippery outside and i hit the gas to hard sometimes and the VDC comes on and limits the engine, making it feel sluggish.

Only suggestions i would have is fuel injector cleaner, make sure your car is warmed up, inflate your tires, and don't drive around with 200LBS of crap in your backseat.

 

Try resetting the ECU and see if that helps. Easy, simple, and free.

 

i average around 18-20mpg, if you're sluggish that means something else is going on.

 

How do i do that? and im comtplating changing my transmission fluid. i doubt it was changed before its a 04 with 45k on it

 

bump for help

 

disconnect negative battery cable for at least few minutues

 

^

ECU RESET: Unplug negative terminal, push on break pedal 3 times, plug back in.