Solution K00585105
Tuesday, August 7, 2018 5:25:18 PM CEST

Mack Models
Mack Model

TE-TerraPro , LR , MRU , GR-Granite , PI-Pinnacle , AN-Anthem , CHU , CXU ,
GU

Engine family
Engine family

MP7 , MP8

Emission Standard
Emission Standard

2018 , OBD2017 , US17 GHG

** SOLUTION **
Title

Mack Chassis - Diagnostic Trouble Code (DTC) P0087-00 Illuminating The
Malfunction Indicator Lamp (MIL) Or Stop Engine Light; Possible Engine Power
/Torque Derate - US17+OBD16 And US17+OBD18 Emissions, Common Model Years
2018 And 2019

Cause

For vehicles equipped with a common rail fuel system, if the fuel rail pressure drops
below approximately 260 bar ( 3370 psi ) for more than 4 seconds while the engine
is running, DTC P0087 ( Fuel Rail System Pressure - Too Low Bank 1 ) will trigger,
causing a torque derate and either a yellow Malfunction Indicator Lamp (MIL) or red
Stop Engine light A low fuel pressure system issue can generate P0087 with or without
the P008A (Low Pressure Fuel System Pressure - Too Low).

Solution

I. Product Improvement PI0883, Special Information
Product Improvement PI0883 has been released as of July 2018. This software
campaign addressed multiple codes and was intended to reduce unnecessary occurrences
for most of them. P0087 is an exception. The Product Improvement, when performed, w
ill not reduce occurrences of P0087. It has been determined that the protection
conditions enabled by an active P0087 were more severe than required.
Vehicles that have not yet had the Product Improvement performed will set a Stop
Engine light and reduce engine torque as a protection measure. After the Product
Improvement has been performed, P0087 will turn on the yellow MIL, and the torque
derate penalty has been reduced but not eliminated, enabling the vehicle to reach a
service location.
If the Product Improvement has not been performed on a chassis, the PI should appear
under the Campaigns section of the Product screen of Premium Tech Tool (PTT) when
first connecting to the vehicle.
- The documentation for PI0883 can be found on the dealer Mack Trucks eMedia.
• Note: There will be a prompt to sign in to the Trucks Dealer Portal site if
necessary.
• Searching for PI0883 will return a link to the bulletin.

If a chassis presents with P0087 logged, it must be diagnosed regardless of whether
the campaign has been performed.

II. Diagnostic Information
P0087 ( Fuel Rail System Pressure - Too Low Bank 1 ) is most likely caused by
restricted fuel filters creating insufficient fuel supply to the high pressure fuel
system. This fault can be intermittent and only set during high fueling demands.
A. If DTC P008A ( Low Pressure Fuel System Pressure - Too Low ) is logged with
P0087:
1. The Main Software (MSW) Part Number of the Engine Control Module (EMS)
should be checked.
a. If the MSW part number is lower than 23033425.P01, software with changes
to the parameter evaluation have been changed and the EMS software should be
updated.
2. If EMS software does not require an update, Guided Diagnostics ( GD ) for
P008A should be followed first, as the issue causing P008A to trigger can be the
cause of P0087.

B. If there are no logged occurrences P008A:
1. Connect the special tooling shown below to measure the fuel supply pressure
before troubleshooting per Guided Diagnostics for P0087.
a. The fuel supply pressure can be measured stationary, but the vehicle may
need to be road tested to monitor the low fuel supply system under load with
higher fueling demands to identify a problem in the low pressure system,
depending on severity of restriction in fuel filters.
b. If no fault is identified within the low pressure fuel system, follow the
troubleshooting from Guided Diagnostics for DTC P008A ( Fuel Rail System
Pressure - Too Low Bank 1 ) as outlined in Step 2 below.

2. Add P008A to the Fault Code list in Step 2 of Guided Diagnostics.
a. In Premium Tech Tool (PTT), click on the Diagnose tab and navigate to Step
2. View DTC information.

b. Click on the Edit list... button in the upper left-hand corner of the window.

c. The Edit DTC list window will appear. Click into the Filter DTCs text box
and type in "P008A".

- There will be a P008A listing for both the ACM and EMS. Do not use the
ACM version of the code.
d. Using the Up and Down arrows, select Active status for the code. Click OK at
the bottom of the window.

e. Click Continue in the bottom right-hand corner of the screen.

f. Make sure P008A is selected and click the Start button.

g. Click on the link for the Function Test. This will provide a series of low
pressure fuel system checks.

h. Proceed with diagnostic steps as normal.
NOTE: There is a possibility of inadequate fuel supply pressure without a P008A
due to the low supply pressure only being evaluated during certain conditions since
removal of the dedicated low pressure fuel sensor from fuel filter housing. The
Aftertreatment Hydrocarbon Injector ( AHI ) fuel pressure sensor is now used on
US17 GHG engines to monitor the low fuel supply system but only during certain
defined conditions.

III. Fuel Pressure, expected pressures (for general reference ONLY, values
below should not be treated as exact)
A. Engine Speed, Normal idle
- The normal operating fuel pressure in a fault free system with unrestricted filters
should be approximately 350 - 450 kPa ( 50 - 65 psi )
B. Engine Speed above 1200 RPM, Stationary
- The normal operating fuel pressure in a fault free system with unrestricted filters
should be approximately 450 - 575 kPa ( 65 - 83 psi )
C. Engine Speed above 1200 RPM, Driving, 100% engine load
- The normal operating fuel pressure in a fault free system with unrestricted filters
should be approximately 400 - 550 kPa (58 - 80 psi)
NA_Sister solutions

K70800169

Campaign code

PI0883

Solution visibility

Dealer distribution

Function(s)/component(s) affected

Function affected

fuel supply , low-pressure circuit , 1 1 0 EMS

Function Group
Function Group

23 fuel system, excluding gas propulsion , 2841 Electronic Control Unit

Customer effect
Main customer effect

diagnostics/methodology , power , fault code/display

Fluid implicated

fuel

Fluid pressure

low pressure

Lights/Messages on

Engine equipment fault warning pictogram ,

information display

warning light

Fault code(s)
OBD 2013 Diagnostic
Trouble Codes

P008A

Conditions
Vehicle operating mode
Frequency of occurrence of
problem

when driving , when stationary
always

Administration
Author

RU4469V

Dealer ID

RU4469V

Last modified by

RU4469V

Creation date

17-07-2018 16:07

Date of last update

17-07-2018 17:07

Review date

01-09-2017 00:09

Status

Published

NA_Author_Group

GTT

Immediate "STOP" danger