Benjamin Jerew is an ASE certified Master Automobile Technician with over a decade of experience in auto repair, maintenance, and diagnosis. In modern engines, the engine control module ECM measures or calculates air flow via either a mass air flow MAF or manifold absolute pressure MAP sensor. Turbocharged engines may use both, but .The manifold absolute pressure MAP sensor on your .L, .L Jeep Grand Cherokee, or Wrangler, or Cherokee, can be tested with a multimeter and a vacuum pump. You don’t need a scan tool!.Order Jeep Grand Cherokee MAP Sensor online today. Free Same Day Store Pickup. Check out free battery charging and engine diagnostic testing while you are in store..Evan Fischer MAP Sensor is an affordable replacement product for your restoration needs replace your damaged MAP sensor with this product manufactured thoroughly to ensure product durability and reliability. All Evan Fischer products are covered by Year Unlimited Mileage Warranty..