PIP4112L

Bulletin No.: PIP4112L
Date: Aug-2013
Subject:
Normal Characteristic - Sag Or Hesitation On Acceleration
Models:
2008-2013 Buick Enclave
2013 Buick Encore
2010-2013 Buick LaCrosse
2011-2013 Buick Regal
2012-2013 Buick Verano
2006-2009 Cadillac STS-V, XLR, XLR-V
2007-2013 Cadillac Escalade, Escalade EXT, Escalade ESV, SRX
2007-2011 STS
2008-2013 Cadillac CTS
2013 Cadillac ATS, XTS
2006-2013 Chevrolet Corvette
2007-2013 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2008-2013 Chevrolet Equinox, Malibu
2009-2013 Chevrolet Traverse
2010-2013 Chevrolet Camaro, Cruze, Express
2012-2013 Chevrolet Impala, Sonic
2013 Chevrolet Trax
2007-2013 GMC Sierra, Yukon, Yukon XL
2008-2013 GMC Acadia
2009-2013 GMC Terrain
2010-2013 GMC Savana
2007-2010 Pontiac G6
2008-2009 Pontiac G8
2008-2009 Pontiac Torrent
2007-2009 Saturn Aura
2008-2010 Saturn Outlook, Vue
Equipped With a Gasoline Engine and Automatic Transmission
This PI was superseded to update model list. Please discard PIP4112K.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
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Some customers may comment on a sag or hesitation when accelerating under the following conditions:
When coasting with a closed throttle and then aggressively applying the throttle. Examples of this maneuver include a rolling stop or a lane change maneuver. In
this type of maneuver, even though the accelerator is applied aggressively, the throttle blade is opened slowly for up to 0.7 seconds to help minimize drive-line
lash and clunking.
Also in a vehicle equipped with a six speed automatic transmission when making a hard, complete stop with a closed throttle, immediately followed by an
aggressive throttle opening the transmission down-shifts may not be completed by the time the throttle is opened. As a result approximately 0.5 seconds of
″zero″ torque may be commanded to allow the shift to first gear to occur.
Recommendation/Instructions
Both of the above conditions are a result of Torque Management and both of these conditions should be considered normal and no repairs should be attempted.
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.
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
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