EFIDynoTuning Forum

I was going over one of my old logs and came across something interesting. Im running the FBGI0. At Idle, Lambse was .68-.71, lambda was .70 and Fuel_Error1 was 1.38-1.49 and KAMS were 1.00 and not moving. Can somebody help me understand what was going on here? Or explain to me how this works?

Heres the BIN

all sounds perfectly normal. Its fully detailed in the fuel write up on the homepage.

Good deal. I was confused because of the lambse being .68-.71. I was expecting lambse to be coming from the fuel table.

OK. After reading the fuel write-up again its still not making sense to me why it would be commanding the .70 lambse. ive opened up the tune and cant figure out table is making is making changes to the base fuel table. The closed loop flag is set and i was at 150 degrees.

in closed loop the ecu has no fuel control so it cant command anything thus the only lambda you should get in closed loop is 1.0 stoich since that is all the o2 is capable of switching at.

lambse will ramp up til the o2 switches lean and then ramp back down to make the o2 switch rich again in a never ending closed loop.

In closed loop the o2 sensors are controlling fuel by switching the ecu cannot command any air/fuel ratio as its purely mechanical by the o2 sensors generating voltage.

sounds like a problem in your O2 circuit.

If Lambse is less than 1 it's waiting for the O2 to switch rich. If Lambse and your Wideband are that close, your fuel is pretty near dialed in. The only thing I can think of that would cause this is your front O2 sensors aren't responding. Watch IEGO11 and IEGO21. they should be switching rapidly around .4V or so.