Check engine light
Thread Starter
Teching In
Joined: Sep 2014
Posts: 5
Likes: 0
From: Phoenix
Check engine light Today my engine light came on and I noticed the engine was running a little warmer then normal at idle, but would drop down to normal when I was driving. I stopped by AutoZone and had them pull the codes; came back as P0521 - Engine Oil Pressure Sensor. Not sure if this would cause the engine to run hot only at idle and not while driving. Ive also noticed my mpg have dropped off dramatically in the past few months, from about 340 miles per tank, down closer to 260 per tank.
Launching!
Joined: May 2013
Posts: 218
Likes: 1
From: CANADA
What pressure is the sensor detecting?
anyway... if it is the sensor... it's a super simple fix... probably one of the easier things to replace that could have went wrong
Here's a GM Service Bulletin Regarding Trouble Code P0521......that maybe able to help you.
GM Service Bulletin: PIP4786: Low Oil Pressure Message Light - Inspect Valve Lifter Oil Filter - (Apr 5, 2010)
Subject: Low Oil Pressure Message/Light - Inspect Valve Lifter Oil Filter
Models: 2007 Cadillac Escalade
Built before April 1, 2006 with 6.2L L92 Engine
(These engines were built with AFM Hardware but the AFM system was disabled.)
2009 Buick Lacrosse Super, Allure Super (Canada Only)
2005-2007 Buick Rainier
2010 Chevrolet Camaro SS
2007-2010 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2009 Chevrolet Impala
2005-2009 Chevrolet Trailblazer
2007 Chevrolet Monte Carlo
2007-2010 GMC Sierra, Yukon
2005-2009 GMC Envoy
2007-2008 Pontiac Grand Prix
2008-2009 Pontiac G8
2005-2009 Saab 97x
With an AFM (Active Fuel Management) V8 Engine RPO: L76, L94, L99, LC9, LFA, LH6, LMG, LS4, or LY5
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concerns: Some customers may complain of a low oil pressure message/light on the dash and a technician may find a Po521 DTC in the ECM.
Recommendation/Instructions: If this concern is encountered, follow SI diagnosis. If it indicates that the Tech 2 oil pressure parameter is low but proper oil pressure is present at the oil filter housing, inspect the Valve Lifter Oil Filter for debris/sludge that could be restricting oil flow to the oil pressure sensor before replacing any parts.
Follow the Valve Lifter Oil Filter Removal and Installation Procedure to remove the filter for inspection. If the filter is plugged, it can normally be cleaned with brake/contact cleaner and light shop air. If it cannot be cleaned for some reason, replace it using the part number listed in the parts catalog. Do not replace the complete Valve Lifter Oil Manifold just because the filter is plugged.
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.
anyway... if it is the sensor... it's a super simple fix... probably one of the easier things to replace that could have went wrong
Here's a GM Service Bulletin Regarding Trouble Code P0521......that maybe able to help you.
GM Service Bulletin: PIP4786: Low Oil Pressure Message Light - Inspect Valve Lifter Oil Filter - (Apr 5, 2010)
Subject: Low Oil Pressure Message/Light - Inspect Valve Lifter Oil Filter
Models: 2007 Cadillac Escalade
Built before April 1, 2006 with 6.2L L92 Engine
(These engines were built with AFM Hardware but the AFM system was disabled.)
2009 Buick Lacrosse Super, Allure Super (Canada Only)
2005-2007 Buick Rainier
2010 Chevrolet Camaro SS
2007-2010 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2009 Chevrolet Impala
2005-2009 Chevrolet Trailblazer
2007 Chevrolet Monte Carlo
2007-2010 GMC Sierra, Yukon
2005-2009 GMC Envoy
2007-2008 Pontiac Grand Prix
2008-2009 Pontiac G8
2005-2009 Saab 97x
With an AFM (Active Fuel Management) V8 Engine RPO: L76, L94, L99, LC9, LFA, LH6, LMG, LS4, or LY5
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concerns: Some customers may complain of a low oil pressure message/light on the dash and a technician may find a Po521 DTC in the ECM.
Recommendation/Instructions: If this concern is encountered, follow SI diagnosis. If it indicates that the Tech 2 oil pressure parameter is low but proper oil pressure is present at the oil filter housing, inspect the Valve Lifter Oil Filter for debris/sludge that could be restricting oil flow to the oil pressure sensor before replacing any parts.
Follow the Valve Lifter Oil Filter Removal and Installation Procedure to remove the filter for inspection. If the filter is plugged, it can normally be cleaned with brake/contact cleaner and light shop air. If it cannot be cleaned for some reason, replace it using the part number listed in the parts catalog. Do not replace the complete Valve Lifter Oil Manifold just because the filter is plugged.
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.
Today my engine light came on and I noticed the engine was running a little warmer then normal at idle, but would drop down to normal when I was driving. I stopped by AutoZone and had them pull the codes; came back as P0521 - Engine Oil Pressure Sensor. Not sure if this would cause the engine to run hot only at idle and not while driving. Ive also noticed my mpg have dropped off dramatically in the past few months, from about 340 miles per tank, down closer to 260 per tank.
