yep, lean cruise i shoot for 16.2:1, anything beyond that and lean misfires can happen due to the variability of the fuel around here. running that high, i managed 37.6MPG on a ~450 mile trip this summer. not bad for a 21 year old midsize car that has since been retired.
PE: 11-12:1 for boost, 12-12.5:1 N/A, depending on the exact engine. there are always exceptions to the rule though.
and NEVER a PE delay.
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