6.6L Duramax MAP Sensor Replacement

How to Replace the MAP Sensor on a 6.6L Duramax Diesel

Applicable Models:

2006 - 2010 Chevrolet Silverado 2500 HD, 3500 HD
2006 - 2010 GMC Sierra 2500 HD, 3500 HD

Applicable Engine(s):

6.6L Duramax diesel LLY
6.6L Duramax diesel LBZ
6.6L Duramax diesel LMM

MAP Sensor Part Number:

ACDelco 2134658 (GM 12623671)

MAP Sensor Seal Part Number:

GM 16194007 (seal is generally included with ACDelco/GM MAP sensor)

The manifold absolute pressure, or MAP sensor measures the pressure inside the intake manifold. It is one of many parameters used by the engine control module to dictate fuel delivery rated based on the current operating conditions. A faulty MAP sensor can therefore have a significant impact on engine performance and fuel economy.

Click any thumbnail to view fullsize, detailed image

MAP sensor location

• Disconnect both negative battery cables.

• Locate the MAP sensor on the upper intake plenum to the passenger side of the alternator.

MAP sensor electrical connector

• Disconnect the electrical connector from the MAP sensor. We also recommend unplugging the electrical connector above the MAP sensor in order to obtain clear access to the retainer bolt.

MAP sensor retaining bolt

• Remove the MAP sensor retainer bolt with a 10 mm socket.

• Carefully remove the MAP sensor from the intake plenum. Rotating the sensor body left to right will help it come out easily without breaking the plastic tip off.

MAP sensor removed from intake plenum

• Clean the mounting surface of any debris and ensure that the MAP sensor seal did not leave remnants in, on, or around the intake plenum. Any debris that enters this hole will end up inside the cylinders of the engine.

MAP sensor closeup

• Remove the retaining bracket from the old MAP sensor and install it on the replacement (slides off and on).

• Lightly lubricate the MAP sensor gasket with clean engine oil.

New MAP sensor installed

• Install the new MAP sensor, once again rotating it left-to-right while inserting into the hole in the intake plenum.

• Once the MAP sensor is fully seated, install the retaining bolt and snug down; do not overtighten as the aluminum threads in the intake manifold are soft and easy to strip.

New MAP sensor installed and electrical connector plugged back in

• Reconnect the electrical connector(s), negative battery cables, and check for proper operation.