I think it wont do much since its waaaaay better to get it from foods.
"Like most drugs, much of l-carnitine taken orally is lost and not
available to the body. The best method for gaining the highest
absorption rate is to acquire it through the diet, not theough
supplements. Dietary l-carnitine (from the actual diet) maintains an
absorption rate of 54-87%, dependent on the dosage, from low (54%) to
high (87%), whereas supplementary l-carnitine is passively absorbed
and therefore only maintains a bioavailability of 14-18% of the dose