Car problems

[Noviskers]

So I know nothing about cars and was hoping someone on here would be able to help me out. I had just bought a 2011 GMC Terrain from Enterprise car rental on monday, I wasn't really able to drive it until today/yesterday though since I went on a trip tues-thurs. But I was noticing today when driving home from work that my gas tank seemed to be emptying really fast. So I switched over to show how many more miles I could drive on my tank before my car died and it said around 303. But in the 4 mile or so drive home from work that number quickly dropped to about 284.

When I got home from work me and a friend were playing video games for a few hours and my car was just sitting in the driveway doing nothing. After about 3 hours my friend left and I decided to go out and check on my car to see if the gauge had dropped more and sure enough it did. It went from 284 to 249 while doing absolutely nothing but sit in my drive way.

I plan on taking the car in and checking things out but am not sure what is going on with my car. So I was wondering if anyone could give me any possible insight as to what is going on with my car? Any help would be appreciated.

[bbr]

I read the topic title as "cat problems",. but that's just me I guess.

It's possible the gas in the tank either evaporated while in the tank, or your tank measurement gauge was measuring a lot more than was actually in the tank because the fuel was "moving around" a lot due to car acrobatics on your end.
After a while it's stabilized and showing the proper value.
Alternatively, the battery might be running low, and causing the value to show lower than it actually is.

A lot of options but to be sure if anything it wrong, simply leave it standing for a while and see if the measure changes every few hours while you're not driving it,.
and whether it increases if you start it up and get the engine going.

As a final option, I;d recommend going to a garage if you fear it's actually leaking fuel.

[ninjapaws]

those gauges are never really acurate unless they are on a completely flat surface. for example in my car, if im facing downhill my gauge reads more gas then i have, uphill i have less gass.

[Deleted]

So I know nothing about cars and was hoping someone on here would be able to help me out. I had just bought a 2011 GMC Terrain from Enterprise car rental on monday, I wasn't really able to drive it until today/yesterday though since I went on a trip tues-thurs. But I was noticing today when driving home from work that my gas tank seemed to be emptying really fast. So I switched over to show how many more miles I could drive on my tank before my car died and it said around 303. But in the 4 mile or so drive home from work that number quickly dropped to about 284.

When I got home from work me and a friend were playing video games for a few hours and my car was just sitting in the driveway doing nothing. After about 3 hours my friend left and I decided to go out and check on my car to see if the gauge had dropped more and sure enough it did. It went from 284 to 249 while doing absolutely nothing but sit in my drive way.

I plan on taking the car in and checking things out but am not sure what is going on with my car. So I was wondering if anyone could give me any possible insight as to what is going on with my car? Any help would be appreciated.

To understand the problem you'll have to understand how the gauging system works

Cracked has a nice article about it <Yah for being lazy> http://www.cracked.com/article_19571...every-day.html

But also how you drive, where you drive, what the milage of said car is, manual or automatic, what options were on at the time of driving (Airconditioner can be quite a fuel drainer)

[aztr0]

If gas has been sitting for a long time in a gas tank it will drain faster. Since you bought that car on the lot, I'm assuming it has been sitting there for some time waiting for a buyer, ignore this if you filled it up and weren't using left over gas from Enterprise. Other reasons could involve a leak in the tank. If you smell gas when you leave your car or if you see leak spots after having car sit over night... but take it to a mechanic as all we could do is guess.

[Noviskers]

Okay thank you everyone for your responses. I don't really know too much about cars so I was just trying to get a general idea of what was going on before I go forward with the next few steps.

[Kulanae]

MPG calculators use an air flow sensor and the float in the fuel tank to calculate possible MPG. The float in the tank is sensitive to leveling issues, and the air flow sensor to temperature and air density. Because the air flow sensor does not take into count things like running AC, the accuracy of the measurement can vary drastically.

If you suspect a problem, the most likely cause would be a gas leak. And the leak would likely be small enough that the gasoline is evaporating rather than dripping so you can see it. Inspect the tank for dark spots which could indicate a slow leak. Inspect the ground to see if there are signs of a leak.

[smelltheglove]

If you suspect a problem, the most likely cause would be a gas leak. And the leak would likely be small enough that the gasoline is evaporating rather than dripping so you can see it. Inspect the tank for dark spots which could indicate a slow leak. Inspect the ground to see if there are signs of a leak.

fuel pump would also be a prime suspect for a leak, but some cars put the pump in the tank now, not sure where it would be on this one. but if it was a fuel leak that significant you'd be bound to at least catch the occasional whiff

[Deatheryn]

Gas doesn't evaporate in a sealed tank, gauges while not accurate don't change that dramatically. First check you gas cap and make sure that it isn't damaged or defective then keep an eye on the pavement under the vehicle for signs of where gas may have leaked then evaporated leaving a faint residue outline of where it was.

Ever heard the term "Drive it like its a rental?" Never by a car from a rental company no matter how good the deal appears to be. I guarantee that everyone of them were beat relentlessly. Sounds like a fuel leak or bad gas cap allowing your fuel to evaporate. Good luck.

---------- Post added 2012-08-25 at 05:39 PM ----------

fuel pump would also be a prime suspect for a leak, but some cars put the pump in the tank now, not sure where it would be on this one. but if it was a fuel leak that significant you'd be bound to at least catch the occasional whiff

Fuel pump is submerged inside the tank.

[smelltheglove]

Fuel pump is submerged inside the tank.

doesnt surprise me, wasnt sure on that model. most are now i believe

[btf]

run the car for a week and see how u do on mileage - and i mean run the car, not just go here and there but take it on a journey, all those mileages you see which cars can do are roughly accurate, but only if your going at optimum speed doing the optimum journey - anything else will effect the readings - if your still getting poor mileage then take it back and ask them to sort it - regardless of where you bought it, even auction houses have to abide by a code of law

[Deatheryn]

doesnt surprise me, wasnt sure on that model. most are now i believe

Yep, all are, domestic anyhow, some will have a secondary pump on a frame rail to maintain pressure but almost all have them submerged. Makes them a joy to change!

[smelltheglove]

Yep, all are, domestic anyhow, some will have a secondary pump on a frame rail to maintain pressure but almost all have them submerged. Makes them a joy to change!

my 98 ram has it like that, and they even put the fuel filter in it, and the filter isnt available on its own. so you need to change the filter you have to buy the entire freaking pump. replacing the fuel filter on my 69 charger (god how i miss that car) cost less than 3 bucks and about 5 minutes crawling under the trunk (for some reason that's where mine was located)

[Deatheryn]

my 98 ram has it like that, and they even put the fuel filter in it, and the filter isnt available on its own. so you need to change the filter you have to buy the entire freaking pump. replacing the fuel filter on my 69 charger (god how i miss that car) cost less than 3 bucks and about 5 minutes crawling under the trunk (for some reason that's where mine was located)

The pumps now are for high pressure 30-60 psi line pressure that is required by the fuel injectors and use the fuel in the tank to cool the pump motor. Old carbed engines only required 8-11psi and therefore didn't need to be cooled as they weren't working as hard. Fuel injection is better than a carb in one scenario and that is 4 wheeling because a EFI engine will run upside down but a carbed engine will not.

Yeah the good old days are greatly missed when maintenance/repair was much more user friendly. Don't get me wrong OBDII is nice but only necessary because all of the bullshit systems they feel the need to pack into a vehicle. All the "luxury" crap that the add only pose more potential problems.
Take a carb over EFI any day, and be very happy down the road when less that half the problems rear their ugly little heads

[chazus]

I had just bought a 2011 GMC Terrain from Enterprise car rental on monday

Is there no warranty on it? I'd just skip the 'help me out' and return it to get fixed/checked out.

Gas doesn't evaporate gallons in a day.

[Forgettable]

This is a 6 year necro.

[draynay]

just a bit of a necro

[Dacien]

Is there no warranty on it? I'd just skip the 'help me out' and return it to get fixed/checked out.

Gas doesn't evaporate gallons in a day.

chazus!

How could you!

How did you find this thread? I have to know!

- - - Updated - - -

This is a 6 year necro.

What if he's still got gas problems?

[Citizen T]

Necro thread. Closing