Car is running too rich fuel , please help

[Hectorb25]

im looking to change and fix a couple of things on my eclipse gst but i am burning rich fuel , anyone has any idea on where to start off , what to start changing ?

 

[agentorange313]

start by searching the forums for threads on this subject:
http://www.dsmtuners.com/forums/newbie-forum/376741-running-rich.html

http://www.dsmtuners.com/forums/maintenance-repairs/371092-running-rich.html

I would start with these parts first:
o2 sensor, upstream and down steam for you obd2 guys
Coolant temp sensor
Thermostat

There is also something called open and closed loop.

The Essential Primer on the Diamond-Star Engine Control Units - Table of Contents

When your car is in open loop it will run rich. Your car might now be entering closed loop. Are you throwing and codes, check engine light?

I am assuming your car is stock, since your profile is not filled out.

 

[Hectorb25]

yeah i really just bought the car and im new to the DSM world.. now the check engine light is on with two codes P0170 and P0120 which are fuel trim malfucntion and the other one i believe its because of the throttle body position sensor,

 

[jdub1992]

Ya i just threw a P0170 on my 96 TSi AWD and I'm positive that its the front O2 sensor since its the only code

 

[immortalmcf]

before you start buying sensors first test them with a multimeter

 

[96awd16g]

How about a boost leak test or you may be chasing your tail?

I was throwing front o2 code and a few others and fixed boost leak and codes are gone and runs like a great.

 

[Str8Tune]

Yes I definitely agree test your TPS sensor and O2 sensor first before you purchase new ones considering both can be relatively expensive... obviously down to the basics if your car is running rich it means too much fuel not enough oxygen so if the sensors are good look for boost leaks/ vacuum leaks good luck

 

[josh1095]

had the same P0170 code. replaced thermostat and it went away. the old one was stuck open just a little bit but enough to keep engine temps down too far. proper engine temperature is important. they are designed to run at a certain temperature. thats why when i hear a honda guy saying "ive got a low temp thermostat, must be atleast another 50whp now" i want to punch him. running a cold engine(lower than designed by the factory for that certain head/piston/comp ratio engine) actually causes you to lose power.
sorry for the rant , but check your temp sensor and tstat

 

[preludeachris]

check it already been in your shoes i bet its an o2...

http://www.dsmtuners.com/forums/maintenance-repairs/419740-coolent-temp-sensor-more-issues.html