I'm trying to find the voltage range for the O2 sensors (front or rear, either bank). I'm getting a range of .03-.90 V, and I thought that looked a little funky. Only reason I ask is because I'm still battling the PO171/174 and decided to do a quick test on the sensors. I also got a failure on the DPFE downstream hose test (verbatim from the scanner TestID $41 Fail, ComponentID $12, Fail High, FFOF not<= 0200, Delta Pressure for Downstream DPFE Hose Test ).
I know that the upstream sensors should be switching rather quickly, but should the downstream sensors be switching about as fast? Also, I've heard that the DPFE sometimes gets condensation in it, which causes a short and a bad reading. This stupid code has me absolutely stumped, and I'm out of ideas. Before anyone asks, I have done a full UIM/LIM rebuild, replaced quite a few vacuum lines, gaskets, and haven't found any leaks. I also did the plugs/wires, filters all across the board, and cleaned the MAF. Could bad O2 sensors, along with the failed DPFE cause a PO171/174, or would that come back as an EGR failure?
I'm stumped for the first time on this car, and am asking for any help/suggestions that any of you have! Emissions are due at the end of the month, and as of now, it will most definately fail!
Thanks,
Sean
