Feeling a little bored and a little lazy so I thought I'd ask this. 6E/modded ARAP. BLMs look pretty good and the car drives good but a bit lean at WOT. O2 #s are around 860. Whats the best way to get them to 900??

 

someone will tell you NB = not accurrate. I would do a WOT plug check instead. If your BLMs are accurrate your PE should fall in line.

 

Yeah you never know with the narrow band, but from what I've seen 900-910mv is a good place to shoot for. On one car with BLMs around 128, wideband was reading high 14's to 1 air fuel so I know it was somewhat accurate. At WOT with air fuels in the mid 11's to 1, o2 is reading around 935 milivolts.

To adjust PE, use the PE % enrichment vs RPM table and add more % where its "lean".

Plug check is best and a wideband o2 as reference is good idea as well.

 

I cant get to the track for T&T due to schedules and I know thats the best way to read plugs. Wideband confirms NB #s. I added 3% to RPM v PE but I guess thats not enough. I will try another 3% and see what happens. Will report back, if the cops dont catch me test driving.

 

It takes a good bit of fuel to really see a change. I have been finding 10-15% PE will change 1 air fuel ratio.

 

Added 5%. Got the NB numbers up around 880. Another 5% should do it.
Something odd happened though. In a 15 minute drive, the would occasionally die for a split second under light cruise conditions and once waiting for a traffic light. Went in a store for 10 minutes, came out, popped in the old chip and the car ran fine going home. Bad chip ? Corrupt bin ?? Hmmmm.

 

Opened the same bin. Added 5% more. Burned it to a different chip. Car ran perfect. No WOT, did not want to push my luck with the LEOs. Other chip must be bad ??