car runs rich when I am driving ( like a normal person) is ok under wot, need to change part throttle fueling too rich, black stuff all over rear bumper , still gets 20 to 22 mpg , what to use in tunercat to help this?

 

If it gets 20-22 MPG, then it seems good. The black stuff on your bumper is probly built up carbon from the exhaust.

Generally with MAF cars you'd change the MAF Tables I *think*. I'm not certain since I use Speed density.

 

why is there so much carbon in the exaust, is that normal ( no cat ) what can I do about it , I'm using the stock maf( de screened) am I at the limits of tunercat. where to look next?

 

I had the same thing, but when i tuned the car on the dyno and made the changes to the wot fuel and did the same to the coolant table +/- the tables it cleaned it all up...when you do the coolant table wot you do the hole tale +/- ...so your fuel is right no mater what temp you are at..

my maf tables are stock.....