burning alot of gas.

[Buniqueny]

hey guys im in new to DSMs. i have a 91 eagle talon tsi awd automatic. ive been burning alot of gas ever since ive purchased the car. i set my trip miles and a full tank was only about 140 miles. some one told me they think a tune would fix the problem but i wanted to double check first. i have new spark plugs and wires and no check engine light is on. ### help all this fuel is makin me broke!!

 

[scott90gsx420]

A tune will definitively help if the cars been modded.. Is it stock or is the car got mods.. If its got mods then what are they??

Also this sounds like a O2 sesnor issue they will only pop a CEL too if they are sending absolutely no signal.

If its still got some voltage being sent too the ecu then no CEL will be triggered but its sending off really bad readings and so the ecu either is trying too correct wrong or is going into limp mode and just dumping fuel..

The limp mode usually triggers a CEL though so id bet your O2 is dying.. Boost leak check wouldn't hurt either that will cause you to run really rich in turn killing gas mileage

 

[Buniqueny]

no its all stock for right now. how do i check for a boost leak? i am a tru noob haha.

 

[scott90gsx420]

Lol check the Vfaqs they have a thread on how to build a tester then you just tighten it up and compress it to like 15psi.. But seeming its all stock that and the o2 sensor are the most likely.. Id be willing to put money on the o2 sensor..

 

[Buniqueny]

ok thanx. im gonna check out the O2 sensor ill let you know how it goes

 

[scott90gsx420]

Ok man let us know if that doesn't fix it we will go from there..

 

[gusu]

A very clogged fuel filter can cause this too. I'd replace it just because it's so easy and it should help fuel economy anyhow.

 

[scott90gsx420]

^^^Well i agree with you on the fact it will help somehow i don't really see how a clogged fuel filter would cause you to run really rich??Please elaborate im not saying it couldn't happen i just don't see how. ive only heard of a clogged fuel filter causing lean conditions.

 

[gusu]

If your fuel filter is really clogged sometimes when there is enough pressure built up it will start flow and then stop again, the problem is you get a stream of fuel instead of a mist. There usually bogging with it, you will smell a lot of fuel too.

 

[scott90gsx420]

oh i see.. Thats makes since i just always figured once it clogged it just wouldn't flow at all or very little.. News too me haha.