P0171 & P0174 Simultaneous setting???
09-13-2012, 01:17 PM
#1
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P0171 & P0174 Simultaneous setting???
So after picking up my new to me 01' F150 w/ 4.2L I had P1471 (the DPFE Sensor) and both P0171 & 0174 codes.
Last night I replaced the DPFE sensor, after testing which it was stuck with high voltage reading. I cleaned the MAS using CRC MAS cleaner. I did note that one of the two MAS wires appears to be bent, but it is still connected on both ends. Reinstalled, cleared codes, started while still warm and no issue.
This morning I start up the truck and within a few minutes both P0171 & 0174 set again (the DPFE code did not, yay!). I stopped and cleared the codes half way to work, and no codes after this. This is the third time I've cleared the codes and while warm they do not reset.
Does this sound more like the MAS? Or off-chance BOTH banks upstream sensors?
Last night I replaced the DPFE sensor, after testing which it was stuck with high voltage reading. I cleaned the MAS using CRC MAS cleaner. I did note that one of the two MAS wires appears to be bent, but it is still connected on both ends. Reinstalled, cleared codes, started while still warm and no issue.
This morning I start up the truck and within a few minutes both P0171 & 0174 set again (the DPFE code did not, yay!). I stopped and cleared the codes half way to work, and no codes after this. This is the third time I've cleared the codes and while warm they do not reset.
Does this sound more like the MAS? Or off-chance BOTH banks upstream sensors?
09-15-2012, 03:51 AM
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After reading a Google document on the Isolator bolts I'm inclined to tackle this in about two weeks. Could this be the case though considering its only when cold and does not reset after clearing codes until fully cooled down?