Not enough info. Need to know the year, make, model and engine.
The MAP sensor is located on the firewall of the engine compartment, right by the stamped VIN number on the firewall..
The Manifold Absolute Pressure sensor is located to the rear of the engine well, slightly on the left hand side. It is on top of the intake manifold.
The Manifold Absolute Pressure (MAP) sensor is located on the firewall side of the upper intake manifold plenum
It does not have a MAF, it uses a manifold absolute pressure (map) sensor. Which is bolted to the front of the throttle body.It does not have a MAF, it uses a manifold absolute pressure (map) sensor. Which is bolted to the front of the throttle body.
On top of the engine, passenger side.
Under the right exhaust manifold towards the rear of the engine.
On the 4.3 engine it is located under the upper intake manifold. The upper intake manifold must be removed to gain access to it.
Assuming this is a 4.3L engine, the fuel pressure regulator is located under the upper intake manifold. The upper intake manifold must be removed to gain access to the regulator.
The engine computer uses manifold absolute pressure (MAP) to calculate how much air is going into the engine. That helps calculate how much fuel to inject.
the sensor is under the exhaust manifold at the rear of the engine
The Manifold absolute pressure monitors intake manifold pressure and ambient barometric pressure. The PCM/ power train control module uses this input signal to determine engine load and adjusts fuel injection duration accordingly.