Running Rich. Ideas?
Thread Starter
Safety Car
Joined: Nov 2007
Posts: 4,537
Likes: 1,403
From: Bethesda MD
Running Rich. Ideas?
I noticed a while back that my average MPG had dropped a couple mpg (both in the city and highway). I don't recall it being a sudden drop. Air filter, plugs and wires are not the culprit. When I logged the car, I noticed my LTRIMs were running pretty consistently in the -8 to -10 range in both banks. I looked back at a log from when I last tuned the car (several years ago) and they were pretty spot on.
Car has LG headers with cats and a mild cam. It was tuned on a MAF only basis so unfortunately I can't switch to speed density and see if the LTRIMs return to normal and rule out a MAF problem. Mileage is a bit over 40k.
Could this be bad O2s on both sides? Any way to visually tell if they are bad? cats gone bad?
I'm looking for ideas on things to check.
Car has LG headers with cats and a mild cam. It was tuned on a MAF only basis so unfortunately I can't switch to speed density and see if the LTRIMs return to normal and rule out a MAF problem. Mileage is a bit over 40k.
Could this be bad O2s on both sides? Any way to visually tell if they are bad? cats gone bad?
I'm looking for ideas on things to check.
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
Clean MAF, change O2 sensors, see what happens. Not unusual for FT's to change some. Different weather, different fuel blends, etc.
Last edited by schpenxel; May 26, 2016 at 09:19 PM.
