My car has 7000 miles. It use to get 28-29 mpg. 310miles per tank. As of late it is averaging 22-23 mpg, 260 miles per tank. what could cause this? I checked for low tire pressure, no problem there. Any ideas?

 

is it winter where u are? or are you driving in traffic all day?

 

I live in California, driving conditions/habits have not changed. I would understand if if was sitting in gridlock traffic, but I am not.

 

I'm in the same boat...I've got 8,500 miles on my 07 Mazda3 2.3 Touring (Sedan) and was averaging 29mpg and now it's down to about 23-25mpg...I'm assuming it's the "winterized" gas mixture they put out during this time of the year...

 

I only have 1300 miles on my car live in Southern Californiaand I get 28 MPG on the road driving around 80 MPH. I just got back from a long road trip and 4 hours non stop each way. It will be interesting to see ifmy MPG changes when I get more miles on the car. You guys check the air filter after all the santa anna's we have had? dust and dirt can cause the engine not to breath right.

 

Ok, we now know there is something going on then with the mpg for mazda 3. Anyone who might have an answer, please let us know! We all know that asking the dealer is a waste of time! I even drive with the cruise control on as much as I can, doesn't help. I put my car in nuetral down steep hills to squeeze out an extra mile. With gas approaching $4.00 a gal we need to find out the cause of this problem!!!

 

that right there may be the problem in fact. the cruise control wastes more gas then regularly driving. are you driving with the cruise control on all the time. what you gotta do is dont use the cruise control unless its a really long time. just drive yourself and your gas mileage will go down. another factor could be that after a long trip you get amazing gas mileage. then come back to do the daily grind. that alters it. when i was driving back and forth to goderich and back i was making 685KM per tank. now its sitting at 540 doing the daily grind. biiiiiiig difference.

 

What I was trying to say was I was trying different techniques to improve my gas mileage. I experimented using cruise control with one tank to see if it would improve my mpg. But it didn't effect it or as you suggested it might of been slightly worse. Believe me the cruise control is not the problem because I barely use it. Sorry for the misunderstanding. I am just frusturated and do not even know where to begin troubleshooting. Dealer says bring it in we they will do a fuel injection treatment on it. You got to be kidding I said. I haven't even had my second oil change. They ask are you using 92 octaine I say no, well thats your problem they tell me. And if you live in las vegas they will say are you using 107 octaine? Yes they do sell it at select gas stations down there. I wonder if it is the new califonia fuel. It is treated with chemicals to burn cleaner.

 

Unless you have a Mazda Speed 3 your dealer is talking out his ***, the owners manual tells us to use 87 octane gas.
Stay outof theArco Stations cause their gas was bad when I lived there 15 years ago and there regular used to be 85.5 octane.

 

I have a 2007 3 sTouring with about 2700 miles, and my gas mileage is absolutely terrible. I mean very bad, like around 18mpg. Is the trip computer completely inaccurate, or something? Because according to the computer, which I reset at every fill-up, this car gets about what you'd expect from an SUV...

(By the way, I do pretty normal driving. Mostly in-town but occasionally on interstates, as well.)