1999 2.4 automatic

Due to my trip not working, I never really check my gas mileage, but it's been sucking gas pretty quickly for a few months now. I checked gas mileage on Friday I came up with just over 19.5 mpg. I may as well drive an SUV! Autotrader rates the 1999 2.4 at 23/33, so I may not be THAT off, but I can tell that the gas mileage for my particular car has decreased.

The temperature outside is typically 30-50F. My driving in this car is aprox 12 miles daily, 30-45mph back road type with a few lights, but not city driving. I may beat on it once a week or so if I'm late to work, but I'm not a typically agressive driver, plus I know I've driven it the same way for the 7+ years I've had it. I did live in the city until this past July & it seems that my gas mileage has been even worse now since I'm on back roads instead of stop & go.

I'm planning on double checking the tire pressure & changing the fuel filter. The air filter cone isn't all that dirty. What else would you folks recommend checking?

Oxygen sensor for sure. That can do a number on your fuel economy.

Thanks 4bangerdeathsquad!

Dumb question - where should I be looking for this? I think I've read there's more than 1, am I close? Would it have any other symptoms? The car runs 100% besides this crappy mileage, no lights, smoke, shaking - nothing.

My husband plans on throwing it in the air this week sometime and working over whatever he can find to check, we'll add this to the list. Thanks!

you have a 9 year old car, 30-50 degrees, and your mileage is 19ish.... sounds normal to me.

yeah there are 2 of them. the primary one is on the exhaust manifold. the secondary "downstream" on is by the catalytic converter. The primary one would be the most likely cause of poor fuel economy. personally I don't think 19mpg for moderate driving is normal for a 4-cylinder. but then again, it depends on the level of service the car has received through it's lifetime. yes 19mpg is a common situation with a car that age but I think that can be "refreshed" so to speak.

Short trips in cold weather will demolish your fuel economy. Our motors are complete pigs until they warm up. In the summertime, I can get 37-39mpg highway, but in the dead of winter on E10 winter gas, making short trips, I average 19-22mpg. Don't think you can switch to an SUV and get the same fuel economy, they're probably getting half that.

2002 Cavalier 2200 5spd

sorry to jack your thread, but i dont seem to get that great of gas mileage with my 00 z24 and was thinking of putting in a new o2 sensor but if it were bad would it not trigger the check engine light??

thanks


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2000 Cavalier z24-5 spd, 2.4L - thinking of selling.....

Thanks for the comments folks

4bangerdeathsquad, I'll pass along the info to my husband. Thanks a bunch! He's got 3 days to give it some attention this week.

The car has been well maintained IMO, always doing what is recommended to maintain and no real problems at all. My husband is a full believer that if you treat a car well & maintain it right, it will last & he's been maintaining my Sunfire for 5 of the 8 years I've had it. I guess it bothers me more too because my 1999 Outback with a 4cyl 2.5 and AWD does way better with gas even though it's heavier & isn't rated as high for mpg. The Sunfire was okay, but it has just dropped off. Gradual decline is one thing, but that's not it. Hopefully it's an oxygen sensor & things go back how they should be. I also noticed that the gas station where I'm going most times I fill up has E10, so that's probably screwing me as well. It's the only gas station remotely on my way to/from work, but I'll be looking elsewhere to get away from E10 if I can. Gas stations here aren't required to mark their pumps, so it's hard to know what you're going to get.