running rich

[873Stang]

running slightly rich, wondering what could cause this???
and sometime if i rev or go wot i can smell raw fuel (nox)
i dont know where to start??

 

[craigwhite89gt]

whats done to the fuel system? injectors? Mass Air?

 

[stangster50]

do you have cats? that will cause it to smell rich also. not having cats i mean...

 

[873Stang]

nothing dont to it all stock besides an elec fan still has factory cats.
i changed my gap from 45 to 56 and that helped alittle.

and i have an autometer air fuel gauge so at idle its in the lean driving it goes between rich and stoch i think is the word.

 

[HISSIN50]

The narrowband gauge can be misleading. I wouldn't make determinations based upon it.
Also, isn't excess fuel HC's?

Check for a vac leak at the MAP sensor (if applicable). If a proper vac signal is not reaching the MAP, it can cause rich running.

Good luck.

 

[vristang]

Start by pulling the codes

There is a link in my sig if you don't have a scanner...

You may get lucky and have the computer tell you exactly what is wrong
jason