Im trying to work out some issues I am having with my AFR. I solved the extremely lean problems in my fuel map. I had to richen up the low MAP areas. Im working on my lean conditions while the ECM is in Lean Cruise mode. Most of the issues are solved, but for some reason the AFR gradually climbs up to the high 16's and low 17's and occationally it will continue to gradually lean its self out to low 18's. It mostly does this on long down hill grades and the 16-17's happen during normal driving. Is there a way I can prevent this? My Hiway AFR is set to a max of 16.5. I am running an EBL flash with TT-1 WB and using TunerPro software. Thanks.

 

You can disable lean cruise by raising enable speed to max,

HiWy - Min MPH

You can disable Decel Enlean by going Open loop Decel,

Option word 3 - Bit 5 - OpDcl

You can disable DFCO by raising enable temp to max.

 

Is DFCO enabled? If so that is it. Mine goes to 22/1 same circumstance.

 

I dont want to disable it, but I do need to control the AFR. It doesnt go int DFCO during this either. Its a very gradual increase and I think I have figured out a direction to try. It does it while in MAP areas of below 30 and 60+, so I have been gradually increasing the fuel map in those areas. I am also going to time how long it takes for the increase to get unreasonable and then set a time limit on the LC.

 

I think I may have found a way to alter it. I changed the DE- TPS% Filter along with some fuel map changes has seemed to help a lot.