Thread: running rich, dont know why

have a 93 SE-R, and have been getting crap gas mileage lately, hooked up consult found my A/F alpha is at about 88% when at about 2k rmps, when it should be close to 100%, O2 sensor is working correctly same with maf, maf has been cleaned, TPS is correct, reset the self learn, made it about 3% worse. not sure what else i should look at or if anyone else has seen this issue if they could lmk what they did to fix the issue.

found this but dont think it has to do with a sending unit, but could E10 be an issue?

http://www.sr20-forum.com/general-sr20/2220-mpg-gone-down-crapper.html

What do you mean alpha, are you talking about the equivalence ratio? If so then less than 1 is lean and not rich? Sorry if I'm confused. If you mean it's the inverse of that then it makes sense.

Do you have EGR that could be not working well? Or FPR going bad?

the EGR is working correctly, every time i pull off a vac to the EGR it pops the check engine, the FPR is working right, not leaking any fuel through it into the vac lines, there is a i guess program when using consult called A/F alpha, at idle its 100% and when you hit the throttle it drops according to how much throttle is given, so say i tap half throttle it will drop to about 50%, but when being held at 2k or so, it should see a spike that would drop down to say 85 or 90% then work its way to 100% because its not needing to cram fuel into the cylinders, like for cruising. and its not leveling back to 100%

i may not be explaining this completely correctly but this is what i got out of it from one of my master techs at my shop.