Getting horrible gas milage. 15mpg on the freeway:(

tuborg25 · Post by **tuborg25** » Sat Jan 09, 2010 9:13 pm

Hey guys,

So here is the deal. On my 2001 se atx. For the past month i have been getting just horrible gas mileage. I get like 15-17 on the freeway and like 13-14 in the city.

I have changed the wires and spark plugs, used those fuel cleaners.
I read on here that it might be the O2 sensor but wouldn't i get a CEL if it was bad?

Any ideas of what it could be?

Thanks

sneakers O'toole · Post by **sneakers O'toole** » Sat Jan 09, 2010 9:28 pm

tuborg25 wrote:Hey guys,
I read on here that it might be the O2 sensor but wouldn't i get a CEL if it was bad?

that's what i was gonna say. i don't think you'd get one unless it was really bad, maybe it's not at that point yet? hows your air filter?

tuborg25 · Post by **tuborg25** » Sat Jan 09, 2010 10:54 pm

sneakers O'toole wrote:
tuborg25 wrote:Hey guys,
I read on here that it might be the O2 sensor but wouldn't i get a CEL if it was bad?
that's what i was gonna say. i don't think you'd get one unless it was really bad, maybe it's not at that point yet? hows your air filter?

Yeah but can a bad 02 sensor lower my gas millage by that much.

I have pretty much a new air filter. I put my CAI couple months ago

Panhead · Post by **Panhead** » Sat Jan 09, 2010 11:04 pm

Its probably your o2 sensor bad. You are suppose to change them every 60k. If the o2 sensor malfunctioned, it will throw a CEL. To answer your question, it will lower MPG's.

Neon4Life · Post by **Neon4Life** » Sat Jan 09, 2010 11:07 pm

have someone check your 02 sensor. check it for the neccessary voltage output. and pop them out to see how they look. yes a bad 02 sensor causes other things to go wrong. so it can be a 02 sensor. just check it before you go out and buy a sensor and then you find out that wasnt the problem.

tuborg25 · Post by **tuborg25** » Sun Jan 10, 2010 3:52 pm

K thnx for the help. I will check my the o2 sensor and will prob change it cuz the car is at 115k and it has not been change it before. Do you guys know a rough price of the sensor?

Neon4Life · Post by **Neon4Life** » Sun Jan 10, 2010 3:55 pm

depends wich one you need.

theres the one after the cat converter and the one befoer the converter.

the one after the converter is $129.99

the one before is $66.99

thats if you go with the OEM sensor. they have universal ones u can buy for cheaper. and im using autozone to find that price. im sure other places would be alot cheaper.

Post by **racer12306** » Sun Jan 10, 2010 4:04 pm

check www.rockauto.com

Panhead · Post by **Panhead** » Sun Jan 10, 2010 4:39 pm

Neon4Life wrote:have someone check your 02 sensor. check it for the neccessary voltage output. and pop them out to see how they look. yes a bad 02 sensor causes other things to go wrong. so it can be a 02 sensor. just check it before you go out and buy a sensor and then you find out that wasnt the problem.

Either way, it should be changed if he has more than 60k on both o2 sensors.

tuborg25 wrote:K thnx for the help. I will check my the o2 sensor and will prob change it cuz the car is at 115k and it has not been change it before. Do you guys know a rough price of the sensor?

Go to www.wholesalemopar.com I got both o2 sensors under $60 bucks.

fixitmattman · Post by **fixitmattman** » Sun Jan 10, 2010 4:46 pm

Panhead wrote:Either way, it should be changed if he has more than 60k on both o2 sensors.

And why is that now? I would really like to hear the explanation for that. If it's working fine it's working fine. No need to change parts arbitrarily. For what it's worth I have 260 000km on my original o2 sensors and still get excellent milage.

Panhead · Post by **Panhead** » Sun Jan 10, 2010 4:54 pm

Because I find it hard to believe that you still get the same milage as if it was new. My MPG's started to drop and it felt sluggish after 65k on my car and my driving habit didn't change. I follow my maintenance schedule religiously.

Post by **racer12306** » Sun Jan 10, 2010 4:57 pm

My car is the same as well with 90k on it.

fixitmattman · Post by **fixitmattman** » Sun Jan 10, 2010 6:21 pm

Panhead wrote:Because I find it hard to believe that you still get the same milage as if it was new. My MPG's started to drop and it felt sluggish after 65k on my car and my driving habit didn't change. I follow my maintenance schedule religiously.

I have a stack of fuel reciepts for the last 6 years I've owned the car that show my milage has remained pretty constant over the years, if not in fact improved with some of the mods. This summer I pulled 49mpg (imperial) out of the car a number of times. The car was only rated at 45mpg new.

I also maintain my car very well, breakdown is not an option.

tuborg25 · Post by **tuborg25** » Sun Jan 10, 2010 7:33 pm

k thanks for your input guys. I will get those sensors changed and i will let you know if it fixes it.

I am hoping thats it cuz i am tired of going to the gas station every 16-170 miles. That's how much i get until my fuel light comes on:(

fixitmattman · Post by **fixitmattman** » Sun Jan 10, 2010 10:07 pm

What's the temperature where you are?

tuborg25 · Post by **tuborg25** » Sun Jan 10, 2010 11:00 pm

It's around 30-40 during the winter time. Nothing extreme we don't even get snow. The pic in my sig is from the pass where i go skiing

Donkeypuncher · Post by **Donkeypuncher** » Mon Jan 11, 2010 9:50 pm

It could possibly be a catalytic converter problem, but there would normally be more symptoms from that.

I'd go ahead and do a full tune up for the car. Plugs, wires, seafoam, injector cleaning (at a shop and not just the gas additive), and clean the O2 sensors of any carbon build up.

Post by **occasional demons** » Mon Jan 11, 2010 11:04 pm

Is the engine also getting to normal operating temp?

The temperature sender could be bad, telling the pcm to run it in rich mode. The pcm may partially ignore the overly rich signal from the 02 sensor due to the false signal from a faulty coolant temp sender.

tuborg25 · Post by **tuborg25** » Wed Jan 13, 2010 12:49 am

occasional demons wrote:Is the engine also getting to normal operating temp?

The temperature sender could be bad, telling the pcm to run it in rich mode. The pcm may partially ignore the overly rich signal from the 02 sensor due to the false signal from a faulty coolant temp sender.

Ya the engine seems to be running at regular temperature. I think the sensor is good because it hasn't change the readings and they are always consistent.

but ya i ordered the 02 sensors, we will see if they fix it when i install them

sidepipe87 · Post by **sidepipe87** » Fri Jan 22, 2010 1:26 am

maybe it has something to do with than not very aerodynamic roof rack.

Post by **occasional demons** » Fri Jan 22, 2010 8:18 am

Meh, roof rack will not have that big of an impact. I removed the one from my XJ, and the mileage did not improve. I could understand 1 to 2 MPG loss, but not 15 to 20ish mpg.

Paul56 · Post by **Paul56** » Fri Jan 22, 2010 9:55 am

Meebee he has a washing machine tied to the roof rack?

Take the washing machine down!!!

hansken_yo · Post by **hansken_yo** » Fri Jan 22, 2010 11:57 am

???

Post by **occasional demons** » Fri Jan 22, 2010 11:58 am

No Paul, if he shuts the lid he'll be good.

The spin cycle haz boost!

BlackRoseRacing · Post by **BlackRoseRacing** » Fri Jan 22, 2010 6:44 pm

ok first of all, if an o2 was failing or is bad it will trigger a cel...
My 00 beater and 02 R/T modded both get atleast 25mpg average. My 00 has 155,000 on the orig O2's. There has got to be something your missing.
Has someone with a DRB scanned the vehicle yet?
I'm assumming you have no CEL...
Any gas leaks?
15mpg is very low for a neon....

woodchuckssuck · Post by **woodchuckssuck** » Sat Jan 23, 2010 11:51 am

roof rack doesnt affect mileage much, even with a 13' tandem kayak strapped to the top, 1mpg maybe on a long trip.

something aint so good...

tuborg25 · Post by **tuborg25** » Tue Jan 26, 2010 1:04 am

Yeah I would take the roof rack off but i use it almost 3 times a week when i go up skiing plus ya it can't not make that much of a difference.

Anyways i got the o2 sensors today i i will prob change then over the weekend.

I was wondering i just discovered that my trany fluid at the lowest point at the dib stick i just never had the habbit of checking that so i added some, but do you guys think that can cause my bad mpg. Just wondering i will find out next time i will go to the gas station.

Thanks for all your help:)

Post by **occasional demons** » Tue Jan 26, 2010 8:22 am

If the ATX was slipping enough to affect your mileage that much, it would be toast by now.

esteinmaier · Post by **esteinmaier** » Tue Jan 26, 2010 9:46 am

hansken_yo wrote:

???

Should have asked for that for Christmas. Would have been the ultimate stocking stuffer.

03blackrt · Post by **03blackrt** » Tue Jan 26, 2010 10:14 am

tuborg25 wrote: I am hoping thats it cuz i am tired of going to the gas station every 16-170 miles. That's how much i get until my fuel light comes on:(

How are you calculating fuel mileage?

I have around 4 gal. of gas in my tank when my low gas light comes on. 2 gal when the gauge hits empty.

2GN.ORG

Getting horrible gas milage. 15mpg on the freeway:(

Getting horrible gas milage. 15mpg on the freeway:(

Re: Getting horrible gas milage. 15mpg on the freeway:(

Re: Getting horrible gas milage. 15mpg on the freeway:(