Manifold Absolute Pressure (MAP) Sensor Replacement

Typical Cost: Low
Mobile Repair? Yes
Typical Lead Time: 24 - 48 hours depending on part availability

What does a manifold absolute pressure sensor do?

The MAP sensor measures the pressure in the intake manifold. The information is sent to the engine control unit (ECU) to determine adjustments to the fueling of the engine and ignition timing..

How does a manifold absolute pressure sensor work and what are the components?

There are many variations of MAP sensors and how they work, but the principal is the same, this is just a very brief overview on what it does.

The manifold absolute pressure (MAP) sensor is a single sealed unit that contains two chambers with a flexible diaphragm in between them. When the engine is switched off, the pressure difference is the same as the atmospheric pressure of the vehicle's location.

Before the engine actually starts, the engine ECU takes a reading from the sensor to determine the current pressure as a baseline. It then monitors the pressure as the engine is running to adjust the fuelling and ignition timing according to the reading.

Typical symptoms that require a manifold absolute sensor to be replaced.

Any issue with the sensors ability to send back the information, be it the sensor itself, the signal wire, a boost leak etc, can give some or more of the following symptoms

• Laboured engine starting.
• Erratic engine idle speed.
• Surging under acceleration.
• Incorrect fueling and engine knock.
• Loss of power.
• Poor fuel consumption.
• Engine Management Light (EML) on

What happens during a manifold absolute sensor replacement?

Changing manifold absolute sensors is a routine repair for all mechanics and can be done both kerbside as well as in the workshop, providing it is safe to do so.
Whilst there are variations between manufacturers, the basics are pretty similar.

The mechanic will;

• Assess the situation by reading the diagnostic codes and checking live data
• Once confirmed that the manifold absolute pressure (MAP) sensor is faulty, continue on to replacing it.
• Once replaced, start the engine and recheck the error codes

What does this repair cover?

Unless otherwise stated, the quote for your brake pads to be replaced will cover;

• The cost of the manifold absolute sensor
• Coming to you
• Fitting of the parts
• Disposal of the old parts (unless you request to keep them)
• VAT (if applicable)
• 12 months parts and labour warranty

What to search for on the ClickMechanic site?

Inlet manifold pressure (MAP) sensor replacement

Associated repairs

Mass air flow (MAF) sensor replacement - Diesel
Mass air flow (MAF) sensor replacement - Petrol

How much does it cost to have a manifold absolute pressure sensor replaced?

The cost of a manifold absolute pressure sensor replacement depends on your car and what parts your car's manufacturer recommends.

Find out what you could save by visiting ClickMechanic
https://www.clickmechanic.com/bookings/car

FAQ’s

Can I supply my own parts?

No, we will not fit customer supplied parts unless they are a brand new item, purchased from a dealership with the receipt as proof of purchase. There is no flexibility over this due to insurance and warranty issues.

What happens if the mechanic finds that the manifold absolute pressure sensor doesn’t require changing and the problem is due to another issue?

In this scenario, the mechanic will provide a no obligation quote for the correct repair. Should you accept this, the mechanic can alter the booking accordingly. If you decide not to go ahead with the alternative repair, the mechanic can change the booking to a call out and diagnostic booking and charge according to the time spent with the vehicle and call out.