2005 gmc sierra high engine pressure
Did the gauge just go to 80 or did it go way past 80? If it went way past 80 then that shows an open circuit somewhere in the oil gauge circuit, if it just went to 80 then it could just be a sending unit. Hook up a manual gauge to find out the actual pressure, if the actual pressure is reading 80psi then the high pressure relief valve has stuck and the oil pump will need replaced, if not then the oil pressure sender is the most likely cause. Replacing the sender is a fairly easy job.
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