Gas milage?

[AlphaBubbles]

I just bought my 98 eclipse gst about a month ago. I noticed that i would have to fill up with around 100 miles on the trip! Ive filled up three times each time being the same. I was also wondering why when i fill up does it click at only 10 gallons. I thought it had a bigger tank then that. If anyone could help me.

 

[jrdrew5]

I have a 97gs-t and I take either 12 or 17 gallons I can't remeber and don't feel bad the most I've ever got out of a tank is around 270. And it cost me 40$ to fill it up.

DSM!

 

[ramsack]

Gas gauges are far from being linear. If you only need 10 gallons, then you still have 7 gallons left. 100 miles from 10 gallons is still horrible. My car is in utter disrepair and AWD and I get 200-220 miles from 7 gallons, 80-90% highway.

 

[2GbTalonGuy]

I would start with doing a tune-up, see if that improves your mileage. If that doesnt help, youve got a bigger problem.

 

[2gawdtsi]

40$ sounds about right for 12 gallons,
when i fill up i usually put around 12 gallons in, which is when my light comes on.


If everything is all tuned up, no boost leaks, you maybe should look into a new o2 sensor

 

[JusMX141]

Fix that problem before you blow your engine...I wouldn't drive the car until it's fixed. You're filling the crankcase with raw fuel if you're using that much gas in 100 miles.

 

[AlphaBubbles]

How would i fix that problem and how would i know if its filling the crankcase?

 

[nek]

Id check that front 02. A faulty 02 could cause you to run rich as hell like I was. Replacing it got me up to ~20 mpg

 

[donniekak]

Gas gauges are far from being linear. If you only need 10 gallons, then you still have 7 gallons left. 100 miles from 10 gallons is still horrible. My car is in utter disrepair and AWD and I get 200-220 miles from 7 gallons, 80-90% highway.

I get 180-220 miles per tank, and i run e85. Its because i run 9:1 pistons, and cruise at 15.5:1 afr's.

 

[JusMX141]

How would i fix that problem

The same way any of us would....track down the problem, and fix it. You created a thread on a topic that none of us can help you fix without the car being in front of us. Start with the o2 sensor, then move to the coolant temp sensor, perhaps the fuel pressure regulator.

how would i know if its filling the crankcase?

It is. I ruined the engine in a 1988 Caravan a long time ago (when gas was cheap) over a bad o2 sensor. Probably drove the van 10k getting around 13mpg; by the time I changed the sensor it had no oil pressure at idle even with 20W50.

 

[FLASH1970]

I get about 25mpg out of my GSX with almost 215K on it. Something is wrong. If there's no check engine light on I would replace the plugs, wires, fuel filter, & air filter. Do a compression test too. I woudln't drive it until it is fixed.

 

[TSi Kid]

i get about 220 with awd and i get on it alot
somebodys running rich

 

[EclipseTical]

start with basic maintenance and check [and replace if necessary] the following:


front o2 sensor
spark plugs
spark plug wires
boost leak test
Compression test wouldn't hurt either; pending those results do a cyl leakdown test

You've only had the car for 1 month correct? You still driving around in boost all the damn time like 90% of new DSMers do when they first get their cars? That will shoot your gas mileage in the foot rapidly.

FWIW i see about ~235-240 out of my 99 GSX depending on my driving habits during that particular tank.

 

[SrKegler]

I put around 2000 miles a month on my 1Gb AWD. My mileage runs around 26MPG running 75=80 on the interstate. You definately have fueml problems/

 

[my dreamt dsm]

I think the max is 15.9 gallons I could be wrong.

I'm also having the same problem after just an intake. I figure something is wrong but I leaning towards my o2 sensor and bad plugs + over heating problems.

 

[Richie]

I have a 95 TSI AWD and get about 12-14 MPG. Did a leak test and fixed the intake leaks. Now I get about 20-22 MPG! Check around the MAF and BOV for leaks.

 

[gsx4357]

ok is the factory gas gauge reliable? is it acurate? ### from what i understood the tank should hold 17 gallons and everytime the gauge shows empty i fill her up and only gets 10or 11 gallons till full...whats wrong?

and for the record i get around 230-240 miles with a full tank and thats without the front o2 sensor (the one in the o2 housing) ### i took it out and need to buy a new one

 

[brian102]

i have a 97 spyder with the 2.4 and i get around 25mpg if i take it easy! around 22 if i run it hard. Everytime i fill up the gauge reads empty but i always put in 10 gallons figured it was a 12 gallon tank always. Have never seen a fuel light on before!

 

[alternativesurf]

98 RS, I get about 24mpg but if Im on all freeways I can hit 32.

 

[solar_eclipse89]

All 1G cars have a 16 gallon (60 liter) tank. All 2G cars have a 17 gallon (64 liter) tank and get anywhere from 19-23 city and 25-33 highway depending on your trim package... I would check your fuel gauge and the sending unit you should still have 7 gallons left and you need a tune up bad if you are getting 10 mpgs

 

[crazysweetguy]

I got 20-25 MPG driving through cities and country roads with a GST.

 

[BMPer4manceDSM]

Our shop built 35R GST gets 24 mpg.

 

[nickk90]

It always takes me about 10 gallons to fill up from E. I've always thought the tank was 12.7 gallons or something along those lines.
I would differently check the front o2 sensor and coolant temp sensors. Do you have any trouble codes popping up / check engine light on ?