Ford Ranger egr malfunction
I have a problem with my egr system on my truck. The code its throwing is p0401. "Faulty solenoid or valve" and " insufficient flow". I replaced the valve, solenoid, and the dpfe sensor. I am still getting this code. I tested continuity to the wire harnesses and have it there. I also tested the vacuum goin to the solenoid and to the egr valve. It shows good to solenoid but doesn't even register going to valve. My book for vacuum tester says if its not in a range for the vacuum to the valve check Thermal switching device. I have called multiple parts store and nobody seems to know how that would be linked. Need help!