Map Sensor Working and Its Applications

Nowadays in current vehicles, the fuel consumption of an engine can be controlled by a set of sensors as well as a computer. This sensor is essential for smoothly running. The control unit of an engine can be connected to several sensors throughout a vehicle. Depending on the data these sensors stops detecting, then the control unit of an engine will start certain functions to make sure that the vehicle’s engine works at its best. This article discusses shat is a MAP sensor, working, how to detect a bad sensor and its applications.

What is a Map Sensor?

The full form the MAP sensor is “Manifold Absolute Pressure Sensor”. The sensor is used in electronic control systems for fuel consumption of an engine. The engines which use a MAP sensor are basically injected by fuel. The various pressure sensors provide instant pressure data to the electronic control unit (ECU) of an engine.

The data can be used to evaluate air density & decide the air mass flow rate of an engine that decides the necessary fuel metering for best combustion. An engine with fuel injected may use an alternate sensor namely MAF sensor which is named as a mass airflow sensor for detecting the intake flow of air.

The information of a MAP sensor can be changed to air mass data with the help of a method like the speed density. The speed density measurement can be done with the speed of an engine & air temperature.

Map Sensor Working Principle

The MAP sensor is an input sensor which detects an engine load and provides a signal which is proportional to the sum of vacuum. After that, an engine computer utilizes this data to alter explosion timing & fuel enhancement.


Whenever the engine works hard, ingestion vacuum falls because of the throttle releases wide. The engine utilizes more air or more fuel to maintain the air or the fuel ratio instability. In fact, once the computer examines a load signal from the sensor, usually it makes the blend of fuel go somewhat richer than regular thus the engine can generate extra power.


Simultaneously, the computer will hold up explosion timing a little to stop ignition that can harm the engine & its performance. Whenever conditions modify as well as the vehicle is traveling with below light load, and then low power is required from the engine.

The choke cannot open extremely wide otherwise may be blocked to cause intake vacuum to enhance. The MAP sensor detects this & the computer reacts by leaning-out the blend of fuel to decrease fuel use & enhances ignition timing for squeezing somewhat fuel economy outside the engine.

Signs of a Broken Map Sensor

The bad map sensor can be detected by the following symptoms.

  • Fuel ratio of lean air and rich air
  • Surging
  • The economy of Poor fuel
  • It cannot work
  • Engine power problem
  • Stalling
  • Misfire & Detonation

To overcome these problems, troubleshoot of a MAP sensor can be done using a simple method with the help of a DMM (digital millimeter) & a hand-held vacuum pump.


The applications of a map sensor include the following.

  • It is used to decide the fuel utilization
  • It is used to decide the fuel delivery
  • Adjusts with the altering environment
  • To inform the RPM variation

Thus, this is all about the map sensor. From the above information finally, we can conclude that this sensor is used to calculate the internal combustion of an engine. They offer multiple pressure information to the ECU of an engine. Here is a question for you, what are the advantages and disadvantages of a MAP sensor?