What is the recommended spark-gap? If gapped wrong would this decrease m/p/g? on 2008 Dodge Avenger

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It is gapped at 35. Still cranks hard.
(3) Answers
(2) Comments
Have fuel pressure tested.
yes. poor gap can effect MPG. possible start system issue. examine ignition coils for damage(charring on boots). still fires up though right?
It still fires up....I will check for damage...Tank you!!!
look in the engine compartment it has the spark gap on the hood, strut tower or by the radiator. hard crank might be low battery or starter going bad
Thank you!