330 miles per tank to 150...wtf? What's wrong?

[SleepingEclipse]

Alright here's the deal guys. When I first got my 93 Eclipse 5sp 2.0L I got about 330-360 miles per full tank of gas. Now, I'm only getting about 150-170 miles per tank. Last year I did the usual tune-up, new filter, plugs, and oil. Well since then I have changed the filter and changed the oil twice. I am wondering what could be throwing my fuel economy down so low? I was at autozone today and read a buncha labels for injector cleaner(I had been thinking about trying some out), but they all seemed to only last a short time and seemed kind of like a gimmick. Any help would be appreciated, any real tips that will work. I'm thinking its time to change the oil, and replace the plugs and wires? Thanks guys!

 

[rstray]

Same thing happpend to me when my fuel injector seals went bad....costed $200 to fix.

 

[project_tsi]

Sound like it may be your 02 sensor taking a shit. I suggest replacing that, and some plugs/ wires wouldn't hurt either. But probably your 02 sensor. They are about $70 new.

 

[aaronm_2003]

Sound like it may be your 02 sensor taking a shit. I suggest replacing that, and some plugs/ wires wouldn't hurt either. But probably your 02 sensor. They are about $70 new.

I don't mean to get off topic here, but I have seen you post up a lot lately and I have never got to tell you how sweet your car is. That FMIC is huge! Like I said, sorry to interrupt, just thought I would give the props.

 

[project_tsi]

I don't mean to get off topic here, but I have seen you post up a lot lately and I have never got to tell you how sweet your car is. That FMIC is huge! Like I said, sorry to interrupt, just thought I would give the props.

Thanks for the compliments. Finally some of my hard work is paying off. Thanks again.

 

[gsxeclipsed]

i am having the same problem with my back up car dsm is still down and will be for along while. i think the gas companies are not only charging us more but making crappy gas. i dunno what the problem is but i have changed fuel filters and plugs and wires. So i would say try that it helped me alittle.

 

[project_tsi]

I dont think crappy gas. Theres rules and regulations that have to be followed when selling gas.

 

[SleepingEclipse]

I get about 98% of my gas from the same station I did last year. I am going to look into the o2 sensor and possibly new wires. I don't think that will be too bad of a fix....I hope. Any other things to look into guys? Thanks so far for the replies! I agree I like that FMIC, I love when the front end is shaved a little bit to show off the giant FMIC.

 

[95DsmTsiauto]

Wow.. how does everyone but me and 2 of my friends get over 220 per tank? I understand your non turbo and only fwd.. I'm awd and turbo and I get SHIT for gas mileage.. A good tank goes to 200 then the Low gas light comes on... MY car is not in bad shape and i don't go over 4k rpms. Unless I'm in a hurry which is only like maybe 20 miles out of a tank.. My one friend has a 1st gen and gets 160 to a tank.. I think its due to the fact that his car needs a tune up.. But mine only has 45-46k.. My v6 mustang gets better gas mileage and i beat the hell out of it.. Although i understand that it doesn't have as much power...

 

[SleepingEclipse]

Wow.. how does everyone but me and 2 of my friends get over 220 per tank? I understand your non turbo and only fwd.. I'm awd and turbo and I get SHIT for gas mileage.. A good tank goes to 200 then the Low gas light comes on... MY car is not in bad shape and i don't go over 4k rpms. Unless I'm in a hurry which is only like maybe 20 miles out of a tank.. My one friend has a 1st gen and gets 160 to a tank.. I think its due to the fact that his car needs a tune up.. But mine only has 45-46k.. My v6 mustang gets better gas mileage and i beat the hell out of it.. Although i understand that it doesn't have as much power...

I drive very conservatively. I don't go over 3.5k rpms, and I drive the speed limit everywhere. (I already got one speeding ticket and don't want another one.) I also have 142,300k miles on my car. I got 28 mpg when I first picked the car up last year, and I loved it! It did have a leaking flex pipe so I replaced the up-pipe, and ever since then my milage has kinda dropped.

 

[siceclipse]

check o2, replace PLUGS and wires.

 

[gixrman]

Wow.. how does everyone but me and 2 of my friends get over 220 per tank? I understand your non turbo and only fwd.. I'm awd and turbo and I get SHIT for gas mileage.. A good tank goes to 200 then the Low gas light comes on... MY car is not in bad shape and i don't go over 4k rpms. Unless I'm in a hurry which is only like maybe 20 miles out of a tank.. My one friend has a 1st gen and gets 160 to a tank.. I think its due to the fact that his car needs a tune up.. But mine only has 45-46k.. My v6 mustang gets better gas mileage and i beat the hell out of it.. Although i understand that it doesn't have as much power...

116k on the clock, do an average of 75-85mph to work and back with several boosted on ramp merges and still get 280-300 miles a tank. Thats with a A/F ratio of 11.5- 10 under boost.

 

[BudmannG]

How do you check the o2 sensor? Is there a link that I can look at. I have searched and still can't figure that one out.

 

[gixrman]

How do you check the o2 sensor? Is there a link that I can look at. I have searched and still can't figure that one out.

Usally it will throw a "check engine" code if not you need some sort of diagnostic scan tool to check the o2 function.