My '01 sable with 125k keeps throwing the P0401 code. I replaced the DPFE with a new one from Rock Auto but the code still reappeared. I applied vacuum to the EGR valve. The poppet valve moved in and out and the idle got rougher, but did not stall. If the EGR is ok then I read on the posts that the tube should be removed and the passages cleaned. Does anyone know the size of the lower large nut? It looks like a tough place to get at and wonder if it will even come loose and what tool to use. Should I soak the various fasteners first? I figured I could remove the upper nut after the lower one is removed and I also remove the EGR with the tube still attached.
Please let me know the right way to approach this.
Thanks.
Please let me know the right way to approach this.
Thanks.