i dont know if i posted this in the right place if not im sorry

well i havent drivin my camaro to much do to the fact i dont have a license but the last time i got gas i got a full tank and iv gone about 20 miles since a full tank and im already at 3/4 of a tank now correct me if im wrong but theses third gens have a 16.5 gallon tank so 1/4 of that if about 4 gallons and 4 gallons gone in 20 miles thats like 4 mpg now ill admit i had my foot in it pretty good for the 20miles but even so that number just sounds so wrong.4mpg?now i know i need a few things for the car like a new fuel filter and i think i need a new temp sensor cause my temp gauge hasent been working but i dont know if that would affect the gas mileage that much but it dose also seems to be running abit rich but i havent goten the ses light.so what do u guys think my problem is and what sould i fix cause im so lost and just wont to get my car running good mostly at this point cause i have to get emissions tested soon when i get the title transferd and it didnt pass last time and i want it to know

 

cars dont get good gas mileage after sitting for a while. For it being that low it might be timing or the gauge could be wrong

 

ya i just cant get it out more till i get my license

 

yea I dont have mine either it sucks. I got my permit so I can take it out whenever i want, with a parent though

 

ya i cant even do that yet i just take it around the block a few times every so often and pray i dont pass eny cops


eny one else might know what my poblem is???

 

You cant expect to get good gas milage, when your driving consists of very short trips. I would guess, that when you get your liscense, if you did a 200 mile highway trip, you would see much better milage.

When you are going on short trips, alot of your "miles" are warming up miles, not even in closed loop. And you are probably frequently stopping. Also, you said you had your leg in it, which doesent help at all.

 

ya that all makes sense it just seem like such a low number

 

Well my buddies LG4 firebird got 6mpg around town driving like a granny

 

dam that sucks

 

Fuel tank sizes tend to vary from car to car. I'm not sure if the TBI 305 cars had bigger tanks or not. But for my car (L98) it's supposed to have a 15.5 gallon tank. But I can't get any more than 13 gallons in. (gauge below E, fuel pipe whining)

Also, they will go for probably 40 miles without moving from Full and then just shoot down to 3/4 rather quickly.

Put some steady mileage on the highway and see how it does.

 

ya ima try that as soon as i get my permint i would have someone do it for me but my parnts dont trust the camaro and i dont trust my sister cause she drives a tade crazy and since the camaro hasent really been gonin eny where its got no insurance and i will nver let eny of my friends drive it but its lookin like i get my permint in about a week or 2

 

There's also the possibility that while it's sitting for those long periods you're loosing some fuel to evaporation. If you have a leak in your tank (around the pump seal, or possibly even the filler neck) or have a gas cap that isn't sealing all the way, you can definitely loose some of your fuel to simple evaporation.

Another place that could do that is the return lines or the line running to the evap. canister. If one of those is loose/cracked/missing, that would also allow fuel evaporation to occur. I have had a couple cars in my day that lost fuel from sitting, and one of these reasons was usually why.

 

I'd also not trust the gauge very much. On my Firebird, it'll sit on F for a long time, and that first 1/4 tank seems to be getting Toyota Prius quality mileage, then it drops like a lead balloon after that.

Go through a full tank, then figure out miles driven and gallons used.

 

Everything you just said was EXACTLY the same situation i was/now in. o.0 I don't know what it could be, but I am going to replace the 02 sensor and hopefully that will fix it. It is not getting the mileage it is supposed to be and my trips aren't too short either. only a couple mods on the car. I replaced some things in it too so eh. We'll see.

 

You CAN'T check MPG with a gas gauge, fill it again and drive it at least 100 miles and refill, then check MPG "miles divided by gallons" do to the uncalibrated gas gauge the first 1/4 tank will usually go 100+ miles on my Camaro, then the gauge drops like a rock. And the gas tanks are 15.5 gal., not 16.5

 

My car does pretty well. Guage reads pretty good too.
I would say to check your temp sending unit. Not to the guage, you have two, one for the computer and one for the guage. If the computer thinks the engine is cold it will run rich. If you only drove 20 miles your o2 would kick in, but the computer only take a reading off of it after the it's hot.

Also could be a leaky injector, or a bad FPR, bad plugs, wires, cap, rotor.
I would agree with you 4mpg is low. My car does a lot better.
My Ford did better then that, and it got 10 mpg on the highway.

One question, do you know what your rear end is geared?

 

well the car has been on little longer of a trip and it seems a tad bit beter still bad tho i think ima need new pugs wire ect... and ill get to that and as far as the rear end i know has nothin to do with it cause it still has the very mpg friendly 2.73(plans to change that tho)but i think once i chang the plugs and wires itl be better

 

I think I would look into how the injectors are spraying, the ECM coolant sensor, and the ignition system.
You should be doing a lot better with those gears.

 

ya the i the injecked and they look fine and i know my temp gauge isnt working so i think i need a new sensor there but i know there are 2 senors and the gauge one has nothing to do with the way the cars runing but maybe if ones bad the other one is 2?

 

Well almost as if by magic I just gave you over 1 MPG increase. Aint I nice.

Your tank is 15.5 gallons not 16.5.

15.5 divided by 4 is 3.875

3.875 gallons used in 20 miles is 5.16129032 mpg not 4 mpg wahoo practically in Prius range.


But as was already stated in this thread the correct way to determine MPG is to fill the tank, drive some distance 100 miles or so, then fill the tank again. Finally divide distance traveled by fuel burned. (amount of fuel purchased the second time) Also the fact that you are claiming 20 miles driven makes the exact number more important. What I mean is that you said 20 miles. Was it 20 or 21?? 20 gives you 5.16 mpg. 21 gives you 5.41. And 19 miles gives you 4.90. thats a half mile per gallon difference between 19 and 21 miles driven. So how sure are you of the 20 miles??

figuring mpg on a cold engine, with your foot in it guessing at how much gas was actually burned and probably only estimating how far you drove is not going to be the best way to do it.

But for the time being you can claim 5.1 mpg and not 4.

 

ya i get what u guys r sayin about the drive 100 miles then fill the tank again and im going to do that when i can but i dont have a drivers licences so i cant really be going on a 100 mile drive and i would get someone elses to drive it but no one trusts the camaro driving that far but me.and i know it was 20 miles cause when i filled the tank i rest the tripometer. ithink when i change the plugs wires and stuff ill be geting a normal mpg