problems with gas mileage and fuel injectors???

[sweetart785]

Hey i have a 2013 genesis coupe 2.0t and it has 3000 miles. So far my gas mileage averages at 17-18 mpg driving around in the suburbs 75% and on the highway 25%
When i bought the car i was told that it should get 21 city 31 highway so something has to be off...
Also when i start the car or drive away slowly theres a ticking or rattling sound coming from the engine. I think its the fuel injectors because that would explain the low mpg.
I took it to my local Hyundai dealership and they said everything was running normally. I still think something is wrong though because i should not be able to hear the fuel injectors so clearly.

Any thoughts...?

 

[mikec]

If one or more injectors is dumping extra gas you'd have black exhaust smoke. And your "check engine" light should trigger since the oxygen sensor feedback would constantly say "too rich" mixture. It's fairly normal for injectors to make an audible clicking sound though normally it's not so loud that you can hear it with the hood shut. Direct injection engines have much louder injectors though; I've personally not heard these yet.

The EPA economy ratings are highly dependent on how you drive. When the testing is done the car isn't driven "as a sports car." It's driven as granny-like as possible to eek out every last bit of MPG. Acceleration is the MPG killer; especially on a turbocharged engine. I'll bet your MPG would improve if you limited your throttle amount to values that don't approach 0 vacuum, let alone positive boost pressure. My 1988 Starion (2.6 liter turbo engine) varies from 13 MPG with a lead foot/lots of around-town acceleration to about 18 MPG when I baby it. It was down to around 8 MPG the one time I took it to a track years ago - a tight road coarse with lots of slow turns followed by hard accel.

mike c.

 

[sweetart785]

That makes sense, and do try to drive it as gently as possible I just didnt think that the MPG could be lower than the EPA estimates. I know on the highway ive gotten 32 mpg doing 70 on cruise control, so I guess ive seen it go both higher and lower. I just really think i shouldnt be able to hear the fuel injectors from inside the car if i have no music on. It seems a bit excessive. I wish there were more of these around in my area so i could compare the sound my car makes to others of the same model.

But seriously though whoever tested it and said it was 21 mpg city driving must have never even hit 1500 rpm. Also idk what city they test in but driving in chicago gets me around 13 mpg. Pretty ridiculous for a brand new car.

 

[homeofstone]

Its a GDI engine which has a noisier injection system than older systems. This is true of all GDI engines.

 

[Jbo]

The six and 5 liter V8 are both gas direct injection motors (GDI) and are noisy at idle even with hood closed. My SWMBO'd even noticed it with a "something wrong with engine " comment. GDI is 1st cousin to diesel injection and hence is noisy. It is however very very efficient, if your highway is good but town mileage is poor, I would suspect operator error or improperly modulated right drivers foot.