Engine code P1781
I posted this under 2500HD Drivetrain thread but no one responded to it, So I figured I had nothing to loose posting it here.
The light first went on a week or two ago, and has been coming on once in a while since then. It only comes on after I start the truck, it has never came on while driving. Any input? Should I update the TCM?
1991 Chevrolet Silverado 3500, 6.2L. 125,000 miles -Sold
2007 Chevrolet Silverado LBZ - R.I.P
2001 Chevrolet Silverado LB7-- Sold
2011 GMC Sierra, LML- 39,000 miles. All stock