What is a MAP sensor and why does your car need one?

If your car has a fuel-injected engine, chances are you have a manifold absolute pressure (MAP) sensor. It’s one of your sensors that controls the amount of fuel injected into the engine, and ensures you get the performance you expect. When you start to notice MAP sensor symptoms, it’s something you need to get checked by a mechanic as soon as possible.

So let’s take a look at MAP sensors, what they do, and when it’s time to get a mechanic to take a look.

What is a MAP sensor?

A car MAP sensor is a device that measures the air pressure inside the engine's intake manifold. It helps the engine control system determine how much fuel to inject into the engine for optimal combustion. Basically, it helps the engine run smoothly by providing information about how much air is entering the engine. If you’re keen to take a look at it on your car, the MAP sensor location is typically on the intake manifold, next to or on the throttle body.

What does a MAP sensor do?

A MAP sensor measures the pressure of the air entering the engine's intake manifold. This information is pretty important, as it helps the engine control unit (ECU) to calculate the correct air-fuel mixture needed for efficient combustion. With the ECU able to adjust fuel injection and ignition timing correctly, the engine can run smoothly and efficiently while it accelerates, decelerates and idles.

What is the difference between a MAP sensor and a MAF sensor?

Cars will generally have either a MAP sensor or a MAF sensor. A MAP sensor measures the air pressure in the intake manifold, while a MAF sensor measures how much air is sucked in by the engine. The engine control unit (ECU) uses this information to calculate how much air needs to be expelled. You’ll also find them in different locations, as the MAP sensor is usually attached to the intake manifold, and the MAF sensor sits before the throttle body.

What are the symptoms of a faulty MAP sensor?

While the check engine light is a sign the MAP sensor is faulty, there are some other symptoms to keep an eye out for. Some of the main failing MAP sensor symptoms include:

If you notice any of these signs, it’s time to give the mechanics at mycar a call.

Can I drive my car with a bad MAP sensor?

You shouldn’t drive a car with a bad MAP sensor as the ECU won’t be able to determine the correct air to fuel ratio, leading to problems like misfiring, stalling, and issues with exhaust gas recirculation.

If you do need to drive, avoid driving for longer periods or distances. The longer you drive with a faulty MAP sensor, the more damage you’re causing your car.

How to test a MAP sensor at home

The first way to test your MAP sensor at home is to physically inspect the connectors and wiring for any melting, cracking or loose connections. When you disconnect the sensor, the pins should be straight and clean with no corrosion or bending. The hose should also be free of damage. You can also use a digital multimeter set to 20V and a vacuum pump to take MAP sensor readings.

How do I perform a MAP sensor replacement?

MAP sensor replacement is something you don’t want to get wrong. However, if you’re confident doing so and have the right tools, it can be done at home. To replace a MAP sensor:

Or, you could make your life a whole lot easier and book in a MAP sensor replacement with your local mycar.

MAP sensor cleaning: how does this work?

A MAP sensor clean involves carefully removing the sensor from the intake manifold. Be careful here, and avoid touching the sensitive components. You will need to use a specialised electronic MAP sensor cleaner or solvent to ensure there is no corrosive touching or damaging the sensor. Spray this into the sensor, let it dry, replace the sensor and you’re good to.

How long does a MAP sensor last?

The average MAP sensor lasts between 100,000 to 150,000 kilometres. However, driving conditions, the make and model of your car and how well the car is maintained can greatly affect its lifespan. By getting it serviced regularly you’ll be able to stay on top of any issues and have them fixed before it’s a problem.

Having MAP sensor problems? Better call mycar!

If you suspect you have a MAP sensor problem, stop driving and call mycar on 13 13 28. We provide upfront quotes on all fuel injection system repairs, as well as Zip Pay and Afterpay to help make budgeting easier. Plus, you can feel confident with our workmanship guarantee, covering your MAP sensor repairs along with anything else you need. It’s all part of the mycar service!