MerCruiser® 8M0087834 MAPT Sensor
MerCruiser® 8M0087834 MAPT Sensor
885165 routes to current Mercury replacement 8M0087834
This is a MAPT (Manifold Absolute Pressure and Temperature) sensor — it combines pressure and temperature sensing in a single unit. This is NOT a MAP-only sensor. Do not substitute a MAP-only sensor (861249A1 / 864856A1 / 8M0186195) for this MAPT unit. Mercury distinguishes these architectures.
8M0087834 is the current Mercury/MerCruiser service number for the MAPT (Manifold Air Pressure and Temperature) sensor used across ECM-555 generation mechanical-throttle MPI engine families. It supersedes the earlier OEM number 885165, which is no longer the active service number.
The MAPT sensor combines two sensing functions in a single assembly: manifold absolute pressure (MAP) and intake/manifold air temperature (MAT). The ECM uses both signals together when determining engine load, air density, operating conditions, and fuel/ignition strategy. This is a fundamentally different architecture from the pressure-only MAP sensors (864856A1 / 8M0186195) used in other MerCruiser engine families — these sensors are not interchangeable.
MAPT-related symptoms can overlap with vacuum leaks, wiring faults, connector problems, temperature-sensor faults, fuel-delivery problems, and other engine-management faults. Symptoms alone do not establish a failed MAPT sensor. Proper diagnosis using the appropriate service documentation is required before replacing this component.
Verify your exact engine model, serial number, and existing OEM part number against the application table below before ordering. If your existing sensor is labeled 885165, that number was superseded to 8M0087834. Note: 8M0087834 may look different from the original part — refer to the part number when ordering.
This MAPT sensor applies to verified mechanical-throttle ECM-555 MPI applications. It is NOT a MAP-only sensor and is NOT interchangeable with MAP sensors used in earlier EFI/TBI, 454 MAG MPI, 7.4L L29, or 496/8.1L applications. Verify your exact engine model, serial number, and existing OEM part number before ordering.
881733 — related intake / MAPT assembly seal reference. Verify exact assembly relationship before ordering separately.
Verified Engine Applications
Application relationships are verified against Mercury Marine primary source documentation. DTS applications are excluded where OEM matrix has blank sensor fields.
Related Service Parts
Service parts associated with this assembly. Verify the assembly relationship before ordering separately.
Associated with MAPT sensor assembly. Verify exact assembly relationship before ordering.
Customers Replacing This Part Also Consider
Related components are shown only for verified ECM-555 mechanical-throttle applications.
MerCruiser® 350 MAG MPI ECM-555 — 350 V8 — 2002–2007
MerCruiser® 350 MAG MPI ECM-555 — 350 V8 — 2007–2008
MerCruiser® 350 MAG MPI DTS ECM-555 — 350 V8 — 2007–2008
MerCruiser® 350 MAG MPI Horizon ECM-555 — 350 V8 — 2007
MerCruiser® 350 MAG MPI Horizon MIE ECM-555 — 350 V8 — 2007
MerCruiser® 350 MAG MPI MIE ECM-555 — 350 V8 — 2007
MerCruiser® 5.7L MPI Horizon MIE ECM-555 — 350 V8 — 2008
MerCruiser® 5.7L MPI MIE ECM-555 — 350 V8 — 2008
MerCruiser® MX 6.2L MPI ECM-555 — 377 V8 — 2004–2007
MerCruiser® MX 6.2L MPI DTS ECM-555 — 377 V8 — 2005–2007
MerCruiser® MX 6.2L MPI Horizon ECM-555 — 377 V8 — 2002–2004
MerCruiser® MX 6.2L MPI Horizon ECM-555 — 377 V8 — 2004–2007
MerCruiser® MX 6.2L MPI Horizon MIE ECM-555 — 377 V8 — 2002–2004
MerCruiser® MX 6.2L MPI Horizon MIE ECM-555 — 377 V8 — 2004–2007
MerCruiser® MX 6.2L MPI MIE ECM-555 — 377 V8 — 2002–2004
MerCruiser® MX 6.2L MPI MIE ECM-555 — 377 V8 — 2004–2007
MerCruiser® MX 6.2L MPI Ski ECM-555 — 377 V8 — 2002–2007
MerCruiser® MX 6.2L MPI ECM-555 — 377 V8 — 2007
MerCruiser® MX 6.2L MPI DTS ECM-555 — 377 V8 — 2007
MerCruiser® MX 6.2L MPI Horizon ECM-555 — 377 V8 — 2007
MerCruiser® MX 6.2L MPI Horizon MIE ECM-555 — 377 V8 — 2007–2008
MerCruiser® MX 6.2L MPI MIE ECM-555 — 377 V8 — 2007
MerCruiser® MX 6.2L MPI MIE DTS ECM-555 — 377 V8 — 2007
MerCruiser® 4.3L MPI ECM-555 — 262 V6 — 2002–2007
MerCruiser® 4.3L MPI ECM-555 — 262 V6 — 2007–2008
MerCruiser® 5.0L MPI ECM-555 — 305 V8 — 2002–2007
MerCruiser® 5.0L MPI DTS ECM-555 — 305 V8 — 2005–2007
MerCruiser® 5.0L MPI ECM-555 — 305 V8 — 2007–2008
MerCruiser® 5.0L MPI DTS ECM-555 — 305 V8 — 2008