Perform the following steps:

Page 9 of 16

Decision
Yes. Diagnostics Complete.

1. Induction cleaning process (IK1201173).
2. Create iApprove for engine replacement
NOTE: Run the cleaning procedure before replacing engine and swapping parts to
new
engine.

8

3. If needed Flush CAC (refer to IK1201175).
4. Check for engine performance issues. Perform 0 to 60 MPH Test procedure below.
a. Using Electronic Service Tool (EST) with ServiceMaxx™ software, go to Session
> Performance
b. Find an open stretch of road where minimum speed limit is 50 MPH or higher.
c. Pull over to the side of the road.
d. When driving conditions are safe and vehicle has reached normal operating
temperature, select the record snapshot icon from the toolbar.
e. Press accelerator pedal fully to the floor and accelerate from 0 MPH to max
allowed highway speed. After 0 to 60 MPH Test is complete, stop recording and
save snapshot.
5. Using an Electronic Service Tool (EST) with ServiceMaxx™ software, use the
playback feature and graph the following signal values from the 0 to 60 MPH Test:

No. Go to performance
diagnostic sheet.

• Time
• Vehicle Speed (MPH)
• Torque: Engine Actual Percent (%)
• Torque: Driver's Engine Demand (%)
• Intake Manifold Temperature (IMP)

Compare snapshot to Figure 3 and associated Graph Analysis below. Is "Torque: Engine
Actual Percent (%)" meeting "Torque: Driver's Engine Demand (%)" and IMP meeting
specification?

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015

IK1201172 ­ EPA 2010 ­ 2013 MaxxForce 7 Turbocharger Step­Based Diagnostics

Step Action
Perform the following steps:

Decision
Yes. Diagnostics Complete

1.
2.
3.
4.

9

Induction cleaning process (IK1201173)
If needed Flush CAC. (refer to IK1201175)
Replace Breather (Refer to 2010 MaxxForce 7 Service Manual)
Check for engine performance issues. Perform 0 to 60 MPH Test procedure below.
a. Using Electronic Service Tool (EST) with ServiceMaxx™ software, go to Sessions
> Performance
b. Find an open stretch of road where minimum speed limit is 50 MPH or higher.
c. Pull over to the side of the road.
d. When driving conditions are safe and vehicle has reached normal operating
temperature, select the record snapshot icon from the toolbar.
e. Press accelerator pedal fully to the floor and accelerate from 0 MPH to max
allowed highway speed. After 0 to 60 MPH Test is complete, stop recording and
save snapshot.
5. Using an Electronic Service Tool (EST) with ServiceMaxx™ software, use the
playback feature and graph the following signal values from the 0 to 60 MPH Test:

Page 10 of 16

No. Go to performance
diagnostic sheet.

• Time
• Vehicle Speed (MPH)
• Torque: Engine Actual Percent (%)
• Torque: Driver's Engine Demand (%)
• Intake Manifold Temperature (IMP)

Compare snapshot to Figure 3 and associated Graph Analysis below. Is "Torque: Engine
Actual Percent (%)" meeting "Torque: Driver's Engine Demand (%)" and IMP meeting
specification?

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015

IK1201172 ­ EPA 2010 ­ 2013 MaxxForce 7 Turbocharger Step­Based Diagnostics

Step Action
Perform the following steps:
1. Induction cleaning process (IK1201173).
2. Create iApprove for engine replacement
NOTE: Run the cleaning procedure before replacing engine and swapping parts
to new
engine.
3. If needed Flush CAC. (refer to IK1201175).
4. Check for engine performance issues. Perform 0 to 60 MPH Test procedure below.
a. Using Electronic Service Tool (EST) with ServiceMaxx™ software, go to Sessions
> Performance
b. Find an open stretch of road where minimum speed limit is 50 MPH or higher.
c. Pull over to the side of the road.
d. When driving conditions are safe and vehicle has reached normal operating
temperature, select the record snapshot icon from the toolbar.
e. Press accelerator pedal fully to the floor and accelerate from 0 MPH to max
allowed highway speed. After 0 to 60 MPH Test is complete, stop recording and
save snapshot.
5. Using an
Electronic Service Tool (EST) with ServiceMaxx™ software, use the playback feature
and graph the following signal values from the 0 to 60 MPH Test:
• Time
• Vehicle Speed (MPH)
• Torque: Engine Actual Percent (%)
• Torque: Driver's Engine Demand (%)
• Intake Manifold Temperature (IMP)

10

Page 11 of 16

Decision
Yes. Diagnostics Complete

No. Go to performance
diagnostic sheet.

Analyze snapshot:
Compare snapshot to Figure 3 and associated Graph Analysis below. Is "Torque: Engine
Actual Percent (%)" meeting "Torque: Driver's Engine Demand (%)" and IMP meeting
specification?

Select Parameters:
1.
2.
3.
4.
5.

Time (s)
Vehicle Speed (mph)
Intake Manifold Pressure (psi)
Torque: Driver’s Engine Demand – (Percent)
a.
The amount of torque the driver is demanding from the engine (Spec: 100%)
Torque: Engine Actual Percent – (Percent)
a.
The amount of torque the engine is supplying (Spec: 94-100%)

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015

IK1201172 ­ EPA 2010 ­ 2013 MaxxForce 7 Turbocharger Step­Based Diagnostics

Page 12 of 16

Figure 3: Analysis Parameters of a Well Performing Truck
Item 1: Intake Manifold Pressure - Remains Above 35psi except for when shifting
Item 2: Vehicle Speed ­ Reaches 60mph after 25 seconds of acceleration
Item 3: Torque Engine Actual Percent - Remains around 96-99% excluding shift points
Item 4: Torque Driver's Engine Demand - Remains at 100% through the entire acceleration

Figure 3 is a snapshot of an unloaded truck performing a 0 - 60 mph run plotted in Microsoft Excel for visual clarity. This is a well
performing engine, taking 25 seconds to reach 60 miles per hour with an initial pedal lag. The truck was unloaded for this recording.
The dips in engine torque are where the truck is shifting into a higher gear. Engine torque percentage typically stays between 96-99%
on a well performing engine.

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015

IK1201172 ­ EPA 2010 ­ 2013 MaxxForce 7 Turbocharger Step­Based Diagnostics

Page 13 of 16

Figure 4:Analysis Parameters of a Truck with Low IMP
Item 1: Intake Manifold Pressure - Remains Below 25psi through the entire recording
Item 2: Vehicle Speed ­ Reaches 60mph after 50 seconds of acceleration
Item 3: Torque Engine Actual Percent - Falls below 85%
Item 4: Torque Driver's Engine Demand - Remains at 100% through the entire acceleration
The data in Figure 4 displays a 260hp box truck with a boost leak in the CAC hoses. Boost pressure is in the low 20’s and took 45-50
seconds to reach 60 mph, with a rolling start and no load. The torque percentage trace of the box truck with the boost leak quickly falls
from specification as the engine rpms rise, with no boost to support it. This can lead to shift hesitations, vehicle speed loss, excessive
regenerations, turbocharger coking/oil passage, etc. The entire AMS system needs to be inspected and clamps tightened to ensure
there are no leaks before investigating the turbochargers.

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015

IK1201172 ­ EPA 2010 ­ 2013 MaxxForce 7 Turbocharger Step­Based Diagnostics

Page 14 of 16

Figure 5: Analysis Parameters of a Derated Engine
Item 1: Intake Manifold Pressure - Remains Above 35psi (Until Derate)
Item 2: Vehicle Speed - Reaches 60mph at the 100 second mark
Item 3: Torque Engine Actual Percent - Falls below 85% and is cycling
Item 4: Torque Driver's Engine Demand - Remains at 100% through the entire acceleration
Figure 5 displays an engine derating due to excessive Exhaust Gas Temperature (EGT). Notice how boost remains in specification but
appears to be surging. Diagnosing an engine surge can be difficult because many--if not all--signals will surge with a similar frequency.
There are, however, two main types of surging and knowing which is present will help with diagnostics.

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015

IK1201172 ­ EPA 2010 ­ 2013 MaxxForce 7 Turbocharger Step­Based Diagnostics

Page 15 of 16

Figure 6: Analysis Parameters of a Derated Engine
Item 1: EGT Maximizes at 1350F, in a sever derate
Cyclic Surge - A slow to fast pace surge with a controlled feeling or electronic sound to it as certain engine systems (EGR,
Turbochargers, ITV, Etc.) come in and out of a derated mode. This is seen in Figure 6 and is typically due to EGT overheats.
Sporadic Surge - Typically this type of surge is not due to controlled minor derates or engine controls; it is a higher frequency and can
be described as bucking. Some instances of bucking have been EOT over heats, wiring issues causing false readings, or cylinder
misfires.
Return to top

REPAIR STEPS
See proper iKNow article or service manual for service procedures. (2010 MaxxForce 7 Service Manual)
Return to top

WARRANTY INFORMATION
Claim Requirements/Approvals:
No approvals or special requirements for this repair.
Warranty Claim Coding:
Group: 12000 - Description
Noun: 135 - Description

Standard Repair Times:
Due to the number of trucks and SRT possibilities, see the individual SRTs linked in each step below.

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015

IK1201172 ­ EPA 2010 ­ 2013 MaxxForce 7 Turbocharger Step­Based Diagnostics

Page 16 of 16

Step

Description

Chassis

Engine

SRT

Hours

1-2

Inspect Intake / Verify Oil Level

See Link

EPA 10 MaxxForce 7

Inspect Intake / Verify Oil Level

See Link

3

Crankcase Pressure Test

See Link

EPA 10 MaxxForce 7

Crankcase Pressure Test

See Link

4

Blow-by Test

See Link

EPA 10 MaxxForce 7

Blow-by Test

See Link

5

Relative Compression Test

See Link

EPA 10 MaxxForce 7

Relative Compression Test

See Link

8

Short Block

See Link

EPA 10 MaxxForce 7

Short Block

See Link

8

Engine Assembly R&R

See Link

EPA 10 MaxxForce 7

Engine Assembly R&R

See Link

7, 8, 9,
Turbocharger Cleaning
10

See Link

EPA 10 MaxxForce 7

Turbocharger Cleaning

See Link

7, 8, 9,
CAC Cleaning
10

See Link

EPA 10 MaxxForce 7

CAC Cleaning

See Link

9

See Link

EPA 10 MaxxForce 7

Replace Breather

See Link

7, 8, 9,
Analyze Results / Snapshot review
10

See Link

EPA 10 MaxxForce 7

Road Test (0-60 MPH, Full
Throttle)

See Link

10

Short Block

See Link

EPA 10 MaxxForce 7

Short Block

See Link

10

Engine Assembly R&R

See Link

EPA 10 MaxxForce 7

Engine Assembly R&R

See Link

Replace Breather

Return to top

OTHER RESOURCES
Master Service Information Site
Return to Top
Hide Details

Feedback Information
Viewed:

3480

Helpful:

17

Not Helpful: 0
No Feedback Found

Copyright © 2015 Navistar, Inc.

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlID... 6/1/2015