Carguy8888

iTrader: (1)

I never thought I would be posting here about gas mileage buuut, my basically stock motor is getting around 15mpg on the highway w/o aggressive driving. I know it’s not a prius but I thought we get in the twenties? Even with the 3.42 gears it is only spinning around 2200 @ 70. It runs great but feels like there is a hole in the tank lol. Is this normal or should I look for something? Could it be the tune? Thanks. Brian.

blackbirdls1

iTrader: (5)

Check your plugs, change your fuel filter, run some injector cleaner when you do your oil change. See if that helps.

Carguy8888

iTrader: (1)

Thanks for listening. New ngk plugs have less then 1000 miles, I seafoamed around six months ago if that counts, I will check the air filter. The wierd part is the car runs amazing, just drinks lol.

RJDio

Its gotta be the tune. My car has a small cam but is tuned and drinks gas like crazy.

Carguy8888

iTrader: (1)

Makes sense, pay to play lol. I was sending my pcm back for what he calls an update and to move up the shiftpoints (after the gear swap).

Billett

Tire pressure is often overlooked too. Wouldn't cause that much of a loss, but while you're at it you might as well fill them up.

LS6427

iTrader: (2)

Don't count out a failing 02 sensor(s)

They will totally KILL your gas mileage. And NO.....you will not always get an SES light or code until they are almost failed or really really in bad shape.

So get a scan to see how they are switching.......

One 02 sensor acting up will cut your mileage "close to" in half.

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Carguy8888

iTrader: (1)

Thank you, did it last Saturday. This is way beyond. tire pressure.

Carguy8888

iTrader: (1)

Ding that is a possibility. What is the name of the scan for them? As someone young would say " your the man ".

LS6427

iTrader: (2)

Just a basic OBDII scan while the engine is running and up to operating temp. Make sure they know what they are doing and can read 02 sensor switching activity.......

If you have a race shop near you, I'm sure they'll do it for you for free.....

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Carguy8888

iTrader: (1)

I do have a guy thanks. When I do it I will repost. I think u got it.

BrainFreezE

iTrader: (2)

What if I don't have 02 sensors on my car and the ses light is on due to that cut gas mileage as well huh?

mjs1012

iTrader: (36)

Why wouldnt you have o2 sensors on your car??

jaxcam02

iTrader: (1)

Hey just something to think about, If you seafoamed the gas tank at all you might want to change your fuel filter, just one more thing to check out if it applies

BrainFreezE

iTrader: (2)

because there is no emissions here in FL and the guy i bought it from just straight piped it. its common here in FL i think a majority of the people I know first thing they do is eliminate cats and dont reconnect the o2 sensors, because the aftermarket pipes i have dont have a connection.

LS6427

iTrader: (2)

You're talking about the REAR 02 sensors......those are not needed, they don't have anything to do with the way the engine runs. BUT....you do need and you must have the FORWARD 02 sensors. Engine will barely be able to run without them, it would be a disaster and you would be lucky to be able to accelerate past about 35mph.

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LS6427

iTrader: (2)

Not having REAR 02 sensors will keep the SES light on....but it will have zero affect on anything related to engine performance. Gas mileage would not matter. Rear 02 sensors are there to just sense the exhaust coming through the cats.......I
I may be wrong, but I think the only code the rear sensors will throw is to let you know you have a clogged cat. The rear sensors cannot change air/fuel parameters. Is just a light.

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LS6427

iTrader: (2)

Yes, definitely a good idea. Sometimes the SeaFoam loosens a lot of crap in the gas tank and it will kill the fuel filter by clogging it up.

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LS6427

iTrader: (2)

Also.....another thing that totally kills gas mileage is a leaky fuel injector. It's a pain to pull them and check them all, but if just one injector has sprung a leak your gas mileage will be TERRIBLE. And not always will you be able to hear misfiring or hesitation because they leak really bad under throttle and the combustion process can eat it up and hide it.

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Carguy8888

iTrader: (1)

Thank you, would it throw a code?