My first thought was vac leak also, so I did the propane check. Didn't yield any results. The only thing that changed between my 10.9 LTFT and 16.4 LTFT was a tank of fuel.
Definitely highest while driving. Maxed out at 16.4. Sitting at a light it comes back down to 10.9. I guess it's possibly a fuel delivery also. I have an AEM 340 LPH E85 pump on order. I though my Walbro 255 would have been enough. It just seems weird that it happened right after a new tank of fuel.
I was just thinking, if I throw some 91 in it, that might bring my LTFT down. Would't that confirm or rule out a fuel quality issue?
