This redirect was nominated at Wikipedia:Redirects for discussion on 29 June 2017. The result of the discussion was retarget.

The proposer knows a lot about Greek letters, and very little about combustion engines..

They were three votes for this redirect not taken into account

I copy here the part of the article to show the non exact sentency "- since none of the items on that page is clearly the preferred target for someone who searches for this term. - Richard Cavell (talk) 22:35, 29 June 2017 (UTC)"

Air–fuel equivalence ratio (λ)

Air–fuel equivalence ratio, λ (lambda), is the ratio of actual AFR to stoichiometry for a given mixture. λ = 1.0 is at stoichiometry, rich mixtures λ < 1.0, and lean mixtures λ > 1.0.

There is a direct relationship between λ and AFR. To calculate AFR from a given λ, multiply the measured λ by the stoichiometric AFR for that fuel. Alternatively, to recover λ from an AFR, divide AFR by the stoichiometric AFR for that fuel. This last equation is often used as the definition of λ:

${\displaystyle \lambda ={\frac {\mathrm {AFR} }{\mathrm {AFR} _{\text{stoich))))}$

Because the composition of common fuels varies seasonally, and because many modern vehicles can handle different fuels, when tuning, it makes more sense to talk about λ values rather than AFR.

Most practical AFR devices actually measure the amount of residual oxygen (for lean mixes) or unburnt hydrocarbons (for rich mixtures) in the exhaust gas.--Mcapdevila (talk) 02:25, 8 July 2017 (UTC)[reply]