The car is giving me a trouble code for "Exhaust Gas Recirculation Insufficient Flow", So I put seafoam in the intake manifold vacumn hose, and in the gas. I reset the codes and drove around a bit, and the light came back on, so I ran the code reader again, and it gives me the same code. What are the possible causes, how common is each, and which component should be checked first?
The car is giving me a trouble code for "EGR Insufficient Flow". Causes? on 2001 Ford E-150