98 chevy express 3500 runs sluggish

Question

Got po174 code replaced map sensor , spark plugs &exhaust gasket check engine light went off and ran better 2 days later light coming on and off and running sluggish again. Someone please help any suggestions

Answer 1

P0174 Fuel trim lean Bank 2

Running fine then ran sluggish, this depends on the fuel injector system that you have, there known to plug up, P0174 is a lean running condition where the ECM then commands the fuel trim rich. Smell the oil dipstick any fuel smell as raw gas, a leaking fuel pressure even though you would think it would set a rich code but not necessarily. A plugged catalytic convertor that is partial plugged would cause a sluggish running. this would set a P0300 and a P0174, what is commonly seen is the side of the intake manifold , where there is a common intake manifold leak where coolant seeps into the intake , any coolant loss, that area should be checked.