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MPG on Altima

How can I improve the MPG milage on my 2008 Nissan Altima, 2.5? It currently has 29K miles and when new would deliver 34 to 37 MPG. Now highway is around 31 to 32.

There are a number of possibilities such as the addition of E10 in your local area since you bought the car as well as variations in MPG calculating methodology or driving habits. The engine should be just about broken in by now, so I doubt if you have an engine problem.

Did you nurture it when it was new and now you zip past the other drivers?

Many things can affect gasoline mileage. A headwind can really knock down mileage. However, one quick thing you can check is that the tire pressure is within specifications as called for by the decal on the left door post. If your mileage has dropped by just this amount under the same conditions, this is the first place to check. I suppose the thermostat may be stuck open and the car not warming up completely, but I would tink that this would cause a big drop in your mileage.

Your car is rated for 23 MPG City and 31 MPG highway. If you are getting 31 or 32 MPG, then you are getting exactly what the car is rated for. What is your methodology for obtaining your fuel economy? The trip computer/MPG display isn’t reliable, nor is just averaging two or three tankfulls of fuel. I’ve never seen an Altima get 34-37 MPG and I used to sell them. Even Sentra would have a tough time getting that kind of mileage.