Cummins 3971106 — Genuine MAP (Boost) Sensor for 5.9L ISB

MPN: 3971106  |  Also Known As: manifold absolute pressure sensor, boost pressure sensor  |  Cross-Refs (ID): Mopar 5139278AA (service ID)

Restore accurate boost readings and drivability on your third-gen. The genuine Cummins 3971106 MAP sensor is the OE replacement for 2003–2007 Ram 2500/3500 5.9L ISB. It mounts on the intake manifold and supplies the ECM with precise manifold pressure data for fueling and turbo control. Many kits include the O-ring for a leak-free install.

Features & Benefits

• OE accuracy restores correct boost/air-fuel calculations and throttle response.
• Direct-fit for the 5.9L ISB intake manifold (plug-and-play 3-pin connector).
• Fixes common symptoms like low power, excess smoke, and MAP-related DTCs after wiring/line checks.
• Genuine Cummins calibration and sealing for long service life.

Verified Fitment (Automotive)

Industrial/Off-Highway: Cummins catalogs 3971106 as a Pressure Temperature Sensor used primarily on Tier-3 5.9L ISB/QSB; verify by ESN for non-automotive engines.

Specifications

• Type: MAP (boost) pressure sensor
• OE Part Number: 3971106
• Connector: 3-pin
• Mounting: Intake manifold (single fastener; O-ring seal)
• Quantity Required: 1 per engine

Often Paired With

• MAP sensor pigtail/repair connector (if the harness is brittle)
• Intercooler/boost hoses & clamps (replace if oil-soaked or cracked)
• Intake horn gasket (if removed during service)

What’s In The Box

• (1) Genuine Cummins MAP Sensor (3971106)
• (1) O-ring seal (included with many OE kits)

Installation Tips

• Key-off; disconnect battery negative. Remove the old sensor and clean the port.
• Lightly lube the new O-ring, seat the sensor squarely, and torque the fastener to spec.
• Clear codes and verify commanded vs. actual boost on a scan tool.
• If DTCs persist, smoke-test for leaks and inspect the harness for 5V reference/ground issues.

FAQ

WILL THIS FIT MY 2003–2007 5.9L CUMMINS RAM?

Yes—3971106 is the OE MAP sensor for 2003–2007 Ram 2500/3500 5.9L common-rail applications.

DOES IT INCLUDE THE O-RING?

Most OE listings include the O-ring. Inspect/replace the seal anytime the sensor is removed.

WHAT TROUBLE CODES CAN A BAD MAP SENSOR TRIGGER?

Common MAP-related codes include P0106 (range/performance), P0107 (low), and P0108 (high). Always verify wiring and boost leaks.

WHAT IS THE MOPAR SERVICE NUMBER?

Mopar commonly references 5139278AA for this application.

IS THIS A GENUINE CUMMINS PART?

Yes—OE Cummins 3971106.