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1997 Chevrolet C3500 Base 7.4L 8Cyl GAS L29 Bank 1 Lean
I have this 97 C3500 with a 7.4l. Every once in a great while on a hot start-up it will run lean on Bank 1, approx 22% fuel trim on bank 1, on and off idle. Symptoms are rough idle and no power. It will continue to run this way until it is shut down and cools off, then it will run normally again. I'm struggling to know what the best test is to do on this vehicle, especially since it is so hard to duplicate the problem.