Hi everyone,

I have a 2007 Ion w/ 78000 miles and was hoping if anyone had any ideas...

From 2007 - 2012 the Ion was great... then I had the fuel pump module crack. Not noticing any performance problems (only smell of gas) and not knowing about the free repair, I stupidly took several months to get the thing fixed. Basically, I waited until city gas mileage began to deteriorate and the car had trouble starting.

They fixed it a while back, and changed the fuel filter, and while everything on that end seems great, the gas mileage still sucks. Crucially, it's just the city mileage (~17mpg) that is bad, my highway is still decent (27, 28 maybe?). Before I was getting 30mpg no matter how I was driving it.

There are no other performance issues. Drives perfectly, just bad MPGs. Any ideas on what could be causing this?

 

When's the last time you had the plugs, wires and air filter changed?

 

Air filter recently. Plugs I think were fine at last check. Not sure about wiring. It's passed NYS inspection though w/no problem.

 

Something does not ring quite right.
I have never owned a car that got 30mpg now matter how I drove it, or any gas mileage that stayed constant in the city or country.
While not exactly true a 2 to 1 difference is about right, city gas mileage is about half or so or country.
My Saturn, a 94 can get 30 mpg on the open road at 70mph with the A/C running. I have never bothered to check the city, it is less. My town and country gets about 24 using the same criteria, about 17 in general and as low as 11 with the A/C running in heavy traffic.
my 1970 muscle car gets 20 on the open road and 10 in town. And the list goes on. Frankly to me your fuel mileage sounds about right when it compares city traffic to open road. And driving around for some time with a fuel pump system that sounds like it should have been leaking some where as fuel mileage can generally only go bad if 1.) the engine is using more fuel and a cracked fuel pump does not relate to that or 2.) a cracked fuel pump and lousy gas mileage would seam to indicate a leak along with dumping fuel out on to the road which if you think about that along with the 45# plus pressure it pumps at you probably are lucky it did not.

 

Check out this link.

http://www.fueleconomy.gov/feg/Power...on&srchtyp=ymm

 

I get
26.4 mixed average
Have gotten as high as
36.?? Hiway
Average hiway is
31.??

I don't have my book with me but those numbers are close.

 

My mileage numbers are in line with RJ. 25-6 in town, 31 on highway. I have a 5 speed auto

 

"Something does not ring quite right.
I have never owned a car that got 30mpg now matter how I drove it, or any*gas*mileage*that stayed constant in the city or country."

I agree with Unc 200% on that. I've owned many cars. My numbers match up with Rj and NG. A bit better mixed, mine is a 5 speed manual.

 

If there has been a major change in fuel economy and depending on where you had the service performed it is possible things were assembled incorrectly. What were they? Dunno.
But if the thing has a number of vacuum lines under the hood, having one incorrectly installed could affect things. And just in case you find one incorrectly installed there generally is another installed wrong too. Why? The incorrect one probably goes where another one is because it is wrong too.

 

Good to hear that my fuel estimates are not totally out of line then.

My fear on getting this checked out is that because there aren't any obvious problems, they will just have to do tons of work to check every little part, perhaps screw something up, and/or give me a huge bill. Is this something that I should even worry about checking out?