My 2005 GMC Canyon Check engine light code indicates faulty O2 sensor upstream. New Delco replacements installed and CPU reset several times. Fine for a short time then code generated. After a few cycles, the check light will go off but will return after a few short cycles.
Always occurs at slow speed to set code. NO or not perceptible drop in economy or performance.
Something else is causing the O2 to set a code....help. GM diagnostics said buy more O2 sensors.....of course NO help to me.
〉 Answered on Dec 16th, 2013 by Barb Petrey, President - DBK Enterprises Inc at Jiffy Lube
What is the actual code they pulled? Were the Delco replacements purchased through a GM dealer? AC Delco does make GM's parts, but unless you get the part from the dealer it is an aftermarket (generic) version of it, and does not necessarily meet GM's specifications.
Most of the time, the codes set by the computer for an 02 sensor are secondary codes, meaning that you have to go through 2 or more drive cycles before the code will reset. It could also be a fuse or a wiring issue to the O2 sensor.
〉 Answered on Dec 16th, 2013 by Helaine Kurot, Owner/Technician at 360 Automotive