Help, My car is eating gas!

[nbodyhome]

In the past couple of weeks, we had to replace the battery in my car - but something weird has been going on, my car seems to be getting 8mph or so (normally 25!) I started it today, and it looks like about 2 - 3 gallons are gone, but only 18 miles has been put on it.

Any ideas? Tire pressure is fine. I have had more problems with this vehicle lately (10 years old, nearly 100k miles). I've been resisting getting a newer car, but my husbands is almost paid off and it would be a MUCH less vehicle payment than his (and I should be able to get it paid off quickly). I really just wanted to wait a few years and pay it in cash, but I haven't felt so comfortable driving it anymore and it's had a lot of issues in the past year.

Thanks!

 

[Hedy]

How old is it?
I don't think it would come on so quickly, but I had the fuel injectors cleaned on my 98/114000 miles car and it's made a differenc in my gas milage.

 

[nbodyhome]

Hi!

Thanks - 10 years old now. But it went from about 25 - 27mpg down to 8 or so almost overnight. No indicator lights are on, and my husband checked it with a scan tool and it didn't show any problems that way.

 

[Darcy03231]

You could have a leak somewhere in your fuel line. I would take it to your mechanic and have them look at it.

 

[bmartin1206]

That's quite a dramtic drop. Do you smell gas? Perhaps a leak. Is performance sluggish? Too much gas being called for from a sensor. Any shady neighbors? Maybe somebody is siphoning of some gas. Get a mechanic you trust take a look.

 

[nbodyhome]

I haven't smelled gas, but I can practicall watch the gas gauge go down on a very short store trip now. Before taking it yet again to get it checked, I am really thinking maybe it's time to get a newer vehicle. I keep having problems with this one. I have had it for 7 or 8 years, it's 10 years old and it's been great - but I haven't felt comfortable driving it long distances (more than about 50 miles away) for several years, and I don't feel good driving it at night and such now either. We put $800 into it nearly a year ago, but it seems to just keep having issues.

(Looking at possibly a Hyundai Elantra).

 

[twinklebug]

That large of a drop overnight with no indicators (leaks, smell or engine noise) is suspicious.

Gas prices are shooting up and I've heard of thieves hitting parking lots around here. Double check where you park and make sure nobody has siphoned your tank. You might want to invest in a lock-cap if you think that might be the problem (although these are a hassle)

Older cars tend to have issues with the gas gauge. Mine will tell me it's between 1/2 to a Full tank for a long time and then I can literally watch the meter drop from 1/2 tank to empty on a trip to school. Keep record of how many miles you've driven (from last fill) to how much gas you're putting in to get a good calculation of your MPG.

 

[nbodyhome]

This is a pretty safe area, I'm home most of the time and I don't know that a thief would just take a gallon? I mean, I can literally watch in 8 miles, my gas go down! It is amazing. But there have been so many issues with my car lately - the car often thinks the lights are still on (or whatever other reasons are for that beeping noise when the door is open). The gas needs to be stomped on heavily for the battery to work properly. I saw a lot of smoke when I started it up today.

I think we're done with the car. I was hoping for 2 - 3 more years, but it's taken a big nosedive this past year. We are pretty sure on the Hyundai Elantra, I'd seen it before and it looks like a very solid, inexpensive car.

 

[Wish I lived in Fl]

That large of a drop overnight with no indicators (leaks, smell or engine noise) is suspicious.

Older cars tend to have issues with the gas gauge. Mine will tell me it's between 1/2 to a Full tank for a long time and then I can literally watch the meter drop from 1/2 tank to empty on a trip to school. Keep record of how many miles you've driven (from last fill) to how much gas you're putting in to get a good calculation of your MPG.

Same thing with my car. I go by the odometer. When I fill up i reset the trip odometer to zero, when the trip odometer gets to 370 miles i know the gas tank is low.

 

[bellarella]

Well you can quickly tell whether it is the gas gauge or an actual problem with the fuel --- once your gauge reads 1/2 tank, go to the gas station and fill it up and see how many gallons you put in. You should have the size of the tank somewhere, so you will be able to see if it actually took a 1/2 tank of gas. If it didn't then it is probably a gauge problem. If it did, then you'd be looking at problem with the fuel line or something simmilar.

 

[mom2alix]

I think what you want to hear is: Go and get a new car.

Seriously, if you don't feel safe driving it, and you can afford to get the newer car - go for it! Your safety and peace of mind are important.

 

[crzy4dsny]

Have your oxygen sensor checked. This controls the oxygen and fuel mixture going into youg car. If it is off your car will suck gas like crazy. They tend to go at about 80,000 to 100,000 miles. I have a 10 year old Toyota Tacoma with 240,000 miles on it. I know my oxygen sensor is bad now because my milage dropped by about 100 miles per tank. I have re-placed it once before. I just don't have the $140 to replace it again right now.

 

[nbodyhome]

I did check by putting gas in the car. Trust me, it's at between 8 - 12mpg at this point, really low!

I also have the issue that to start the car, I sometimes have to start it with the gas pedal down when starting it (just to get it going). I had a lot of smoke come out of the back today when I did that.

I actually haven't felt comfortable for a few years to take the car out of a 50 miles or so range. My husband wanted me to have a new car in 2004. I said no, I'm too cheap. But it's starting to be one thing after another, and it'd be nice to have something trustworthy and where I can visit my family occasionally in Tampa too, I can't do that with my car.

Thanks everyone! Nothing about a sensor has gone off in the car - but who knows, the car is just not what it was (really, since last year is the worst).

 

[twinklebug]

I'm not a mechanic but I'm positive smoking is never healthy, for neither human nor machine.

 

[swilshire]

With the cost of gasoline so high, I'd RUSH to my favorite mechanic and let him/her figure it out. It might be something simple. If it's an expensive repair, then you decide if it's time for new wheels.

Sheila

 

[wdwfamilyinIL]

These are simple, but can make a big difference. Fuel filter, change the oil/filter, air filter, new spark plugs and wires, and some fuel injector cleaner. We have to do this on a routine basis, or I lose a good 3-4 mpg on my van.

 

[Scrap'nPatty]

These are simple, but can make a big difference. Fuel filter, change the oil/filter, air filter, new spark plugs and wires, and some fuel injector cleaner. We have to do this on a routine basis, or I lose a good 3-4 mpg on my van.

I aggree with this 100%
You can add the fuel injecter cleaner every third to forth tank of gas.
Add it first then fill up.

 

[matt f]

OK, you don't say what kind of car or what year (unless I missed it ) but I assume it's a new-ish model with fuel injection and computer controlled mixture on a closed-loop system. i.e. it has an oxygen sensor on the exhaust path to adjust the fuel mixture going into the engine.

If you dropped from 25 mpg to 8 mpg, that's way too much of a drop for the engine to still be running OK and pushing that much gas through it. Your fuel mixture would be so rich that the engine would run like crap, your "check engine" light would be on, your catalytic converter would be destroyed, and it would be smoking all the time. The fact that it smoked on startup indicates that it was rich for a moment because you pressed the gas when starting it, which is what it SHOULD do (smoke), and the fact that it's not doing that all the time tells me that the all the extra gas is NOT getting to the engine.

So.... I'll bet you have a leaky fuel line somewhere between the gas tank and the engine. Probably around your fuel pump if it's mounted under the car in the back by the gas tank. I'm also betting that the leak is after the pump, because it's only leaking when the car is running. This is good news if I'm right because it's very inexpensive to fix. It's probably a cracked hose or broken hose clamp. Worst case would be a leaky fuel pump.

You didn't mention whether or not you're smelling gas, but you would definitely be smelling it - only when the engine is on.

Try this: Start up the engine and let the car idle. Look around under the car for leaks. smell the exhaust and see if it smells like exhaust or fresh gasoline (like in a gas can). If you see gas leaking onto the ground, that's your source.

When is the last time you had the fuel filter replaced? If it's the original fuel filter, it's probably clogged and has caused a leak in that area.

Of course, if you're getting a new car anyway, and it looks like you are, I LOVE my new Honda Accord. $17 grand with lots of options. 33 mpg.

Good luck!!

 

[daisax]

If you're really leaning towards getting a new one and it's worth anything at all in the Kelly blue book, I'd say go for it.

I was trying to eek my way through the Spring (and maybe Summer) on my 145K mile Subaru. It was running absolutely fine -- slower on the pickup, maybe a little louder, but sound and safe.

A few weeks ago the headgasket blew -- it went from $2500 Kelly blue book to needing $2900 worth of repairs. They made a token offer for it, but had I turned it in the week before I would have made out at least a thousand ahead, and probably more towards the new car I was basically planning on soon anyway.

I'm not bitter -- if I'd gotten another 6 months out of it it would have been worth it, but...

 

[mickeyfan2]

A person is taking your gas.