PIP5244

File in Section:
Service Bulletin
Bulletin No.:
Date:
PIP5244
November, 2014
PRELIMINARY INFORMATION
Subject:
Poor Fuel Economy
Models:
2010-2014 Chevrolet Equinox
2010-2014 GMC Terrain
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Some customers may have a complaint of poor fuel economy, the recommendations in this document will provide
assistance in accomplishing a fuel economy evaluation.
Recommendation/Instructions
The following procedure will serve as a testing aid to gain the most accurate fuel economy (MPG) results
The Initial Fuel Economy Evaluation:
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Obtain a detailed description of our customer’s driving habits on a daily basis, such as miles driven, roads
taken, and speeds driven.
Check for any stored DTC codes
Check all four tire pressures, you can use the DIC (if equipped) because it is accurate. If the vehicle (and tires)
are cold and pressures are 33 or less, inflate to 35 psi. If the vehicle warm (put hand on tire to determine) and
pressures are 35 or less, inflate to 37 psi
For front wheel drive, raise the vehicle to make sure rear wheels turn freely. In some cases, park brake drag
has been identified. Adjust/repair as needed.
Document temperature and climate conditions, note the current seasonal fuel blend used
Advise our dealer that top tier fuels are preferable when and where available. They help keep fuel injectors and
intake valves clean which provides for optimal fuel economy, performance and reduced emissions. This
information can be found in service bulletin #05-00-89-072C
Actual Driving Evaluation:
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Fill the tank with fuel using 3 click procedure. Add fuel until the pump nozzle shuts off automatically. Count to 5
and continue filling till 2nd pump shut off. Count to 5 and do one last fill until 3rd shut off.
Record odometer and reset trip odometers
Find a flat road where you can maintain a steady state speed for 5 miles (this may or may not be possible
depending on where you are located). In those cases, find a roadway that will at least avoids large hills (rolling
hills are OK if there is as much “up” as there is “down”).
Note any wind conditions such as head wind, tail or cross wind, and how strong or weak.
Bring the vehicle up to speed, from 50 to 65 mph whichever makes the most sense with traffic and road speed
limits and set cruise control.
Reset the Average Fuel Economy button on the DIC (if equipped) by holding the check mark / reset button
down until the display on cluster reads “22 mpg” (on Equinox/Terrain models. This is the “seed” value that the
system starts with and then learns the real fuel economy from there. You should see the display change pretty
quickly (upward) initially. It takes several miles (5 or so) for it to stabilize in steady state driving and give a true
recordable value.
On 4 cylinder Equinox/Terrain modes, at 55 mph, you should get 36 mpg, at 60 you should get 33 mpg on
average.
Try different speeds or conditions, just reset the average fuel economy read out and you will take data from that
point. Once again you need to go several miles before it reflects what you are currently getting for fuel
economy since the reset.
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If enough drive miles are accumulated, top off fuel tank (again follow the procedure in step #1) and use the
same fuel station and pump. Record the odometer reading and mathematically calculate the fuel mileage from
the gallons pumped.
Observe, record and investigate any vehicle performance issues such as a rough idle, excessive vehicle drag
when coasting, and/or poor drivability.
Follow-up:
We highly recommend that personal follow-up with our customer is critical. Not by phone, text or e-mail. Provide the
complete road test findings to the customer to ensure a satisfactory level of understanding of the test and its results.
Note: In most cases a small amount of city driving will bring average fuel economy down quickly. Customers should
be made aware of this fact.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is
resolved without completing every step, the remaining steps do not need to be performed.