Fuel Trim?

[sleepin89]

Could somebody please explain the deal with the short term/long term fuel trim deal, Whats rich and whats lean, and were should mine read at half and full throttle? Im trying to diagnose a problem so any advice would be greatly appreciated.

 

[jstreet0204]

KAMRF(x) = Keep Alive Memory Reference for 'x' Bank
LAMBSE(x) = Lambda or commanded fuel for 'x' bank

KAMRF is also refered to as Long Fuel Trim (LFT)
LAMBSE is also refered to as Short Fuel Trim (SFT)

Think of KAMRF as learning, and learning take time hince the name Long Fuel Trim.

Think of LAMBSE as instantaneous reaction of the Oxygen senor, hince the name Short Fuel Trim

If everythings was perfect, at part throttle LAMBSE should be at 14.7 roughly and KAMRF's would be 1

But nothing is perfect and you will see these numbers fluctuate as the computer adapts and compensates for what it is seeing with the o2's.

Under WOT, only KAMRF is applied not learned.