PIP5244A

Bulletin No.: PIP5244A
Date: Nov-2014
Subject:
Poor Fuel Economy
Models:
2010-2014 Chevrolet Equinox
2010-2014 GMC Terrain
U.S. Models equipped with 2.4L RPO LAF or LEA and Front Wheel Drive
This PI was superseded to update United States Only Under Models. Please discard PIP5244.
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:
•
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:
•
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
1
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.
•
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.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
2