Poor Fuel Economy

[ecrosman]

I have a 2009 Pontiac Vibe 2.4L Base FWD with 127,000 miles and love it except...I have noticed how bad the fuel economy is; 18 mpg city and 23 mpg highway. I have only had it for a couple years now and it has never improved. There are no slippages or any other noticeable problems (no check engine light). I did change the spark plugs but that made little to no difference. Any idea on the problem? Possibly O2 sensor? All answers welcome! Only part of the car I don't like and it is supposed to get ~26 mpg city and 32 mpg highway. Thank you!!

[Bookworm]

That is low, even for city driving in Houston, with our horrible 'EPA' mandated low mileage gasoline.

My first thought would be the MAF (Mass Air Flow Sensor)

Second would be the wrong spark plugs. It turns out that the Vibes are VERY picky, and if you put in the wrong ones, they run, but not as well. I found that out in 2004-5

That's about all I can suggest, as I have no experience with the post 2008 Vibe engines.

I've also noticed you posted this in three forums, so it might be worth consolidating them. You also haven't said where you might be; there might be someone reasonably close by that can assist.

[ecrosman]

I'm new here so I didn't know where to post it. I live in Iowa City and only use Costco Top Tier gasoline.

[Caretaker]

Don't ask my why, but my Corolla Vibe hates Costco gas. Every fill-up over the past 5 years has resulted in rpm shuttering when coming to a complete stop. I can't explain it other than maybe my car doesn't appreciate waiting in tortuously long lines just to get a fill-up (and no squeegie to clean the windows)

[Bookworm]

I'd try a tank or two of something else, just to see. The gas shouldn't make that much difference, however.

[ecrosman]

I have tried other gas from Kum & Go and Hy-Vee but they don't seem to last as long.

[Bookworm]

What about Chevron, Exxon, or Shell?

[ecrosman]

Don't think we have any near by

[zbyers]

What about Casey's or the Route 66? When we lived in Kansas, their gas seemed to be reasonable.

[ecrosman]

Casey's gas is not good!

[zbyers]

can't be any worse than what you've been using. *shrugs*

[cptnsolo77]

First thing I would say is....hows your driving style ? Are you easy on her ?

This is what I would do :

- change driving style if needed

- check tire pressure FIRST...i tend to lose MPG when pressure is low. Mine is at 37 PSI....5 PSI
above reccomended pressure

- clean MAF sensor, TB, IACV and air filter if needed

- check if brakes are dragging

- update us

[tpollauf]

I have a 2009 Pontiac Vibe 2.4L Base FWD with 127,000 miles and love it

First off ... welcome to GenVibe

I didn't see where you mention the transmission? I ask this because in my household we have exactly what you have and in both trannys (one auto, one manual) so I can compare them against each other. The other issue seeing how you've owned it for a couple years now, is it one of the few "oil burning" 2.4L engines out there? We have one in our fleet and the mileage is not that great (son's car, the automatic, and he beats the S H I T out of it ... bad driving behavior)

The auto probably gets only low-mid 20's combined, whereas the manual gets 29 combined over the past ten years

Do you have a history of who owned it prior to yourself and if it had any mechanical issues?
More details and maybe we can better help diagnose your problem.