The MAP (manifold absolute pressure) sensor has nothing to do with your GPS. It is one of the controls on an engine that when it fails causes severely poor engine performance. It also will turn on the engine lite. If your engine light or idiot light as it is affectionately called comes on than going to a competent mechanic for a diagnosis is your safest and most cost effective bet.

Ford fuel injection MAP

A MAP is one of the sensors used in an internal combustion engine’s electronic control system. Engines that use a MAP sensor are typically fuel injected. The manifold absolute pressure sensor provides instantaneous manifold pressure information to the engine’s electronic control unit (ECU).

The quantity that the manifold absolute pressure determines is used to meter fuel. The amount of fuel required is directly related to the amount of air entering the engine. The mass of air is directly proportional to the air density, which is directly proportional to the absolute pressure and inversely proportional to the absolute temperature. Engine speed (RPM or revolutions per minute) determines the rate, at which air mass is leaving the intake manifold and entering the cylinders.

Testing: With OBD II standards, we start by hooking up a scan tool to the vehicles OBD (on baord diagnositics) adapter to test the EGR (Exhaust gas recirculation) valve for functionality during driving. Some manufacturers use the MAP sensor to accomplish this. In these vehicles, they have a MAF (mass air flow) sensor for their primary load sensor. The MAP sensor is then used for logical checks, and to test the EGR valve. The only accurate way to do this is during a deceleration cycle of the vehicle when the current vacuum in the intake manifold is at it’s highest level. During this high vacuum cycle the PCM (Pulse-code modulation) will open the EGR valve and watch the MAP sensor’s values.

Got it? Ha!

That is enough for today. The bigger point here is that if the engine lite comes on and or your car stops performing well, do yourself a favor and go to a competent repair shop. If you find your engine has failed or is in need of dire repairs call GotEngines.com at 1-877-268-0664 for a strategy on how to choose the finest pre-tested rebuilt, used or brand new engines. Subscribe to our blog at GotEngines.com Blog for all types of educational and helpful automotive and light duty truck information, in terms you will understand.