Nerologic

iTrader: (6)

As stated my EVO suddenly started to run rich.

I noticed it a few weeks ago when the muffler got ALOT deeper/louder at idle. And from what i know that means running rich. But not until today did i see my gas go to crap. I got about 100 miles out of 3/4's of a tank (mainly freeway miles)

I am going to reset the ECU and check the plugs once i get up tomarow morning (like many archived threads suggested), and if that doesnt help mess with the MAF, but i rather not mess with the MAF.

The car just has a 3' turbo back w/o a cat. But i was getting decent milage with the turbo back until yesterday.

What else could it be, would a fauled o2 not cause a CEL???

If so how would i check a o2??

The car only has 22k so i dont know how they would be fouled/bad already

Also im not throwing any codes and the car runns fine....

Any ideas??

Ted B

iTrader: (6)

If the car is getting poor fuel economy at part throttle operation, an O2 sensor is a likely culprit. Don't just look for a CEL, but scan the codes. Don't fiddle with the MAF.

Nerologic

iTrader: (6)

yeah im going to hook up a code scanner today at my buddies work, hopefully that will help me out a bit.

I already checked the plugs and i reset the ECU but im not sure if it did anything, il find out in a little bit when i take it out for a drive.

The plugs were dark, but i doubt they were fauled either way im getting new ones just to make sure.

As for the MAF i have that like as in a last resort type deal, because i didnt want to deal with that to begin with.