Quote:
DTC 335 indicates the PFE/DPFE sensor is out of Self-Test range.
Possible causes:
-- Damaged PFE/DPFE sensor.
-- Obstructed pressure inlet hose(s).
-- Garage exhaust ventilation system affecting PFE/DPFE sensor operation.
NOTE:
PFE/DPFE system can sense a lack of pressure in the vehicle exhaust system. An efficient garage exhaust ventilation system that is installed during Key On Engine Off (KOEO) DTM may generate a DTC 335.
l Remove garage forced ventilation system and properly vent to atmosphere.
l Rerun KOEO Self-Test.
l Is DTC 335 present?
Yes
GO to �«DL9�».
No
ADDRESS other DTCs. If none, CONTINUE with �«Quick Test�».
DL9 CHECK PFE/DPFE SENSOR PRESSURE INPUT HOSE(S)
l Remove each pressure input hose from PFE/DPFE sensor.
l Inspect each hose and PFE/DPFE sensor inlet(s) for blockage.
l Is blockage present?
Yes
SERVICE as necessary. RERUN �«Quick Test�».
No
RECONNECT pressure input hose(s). GO to �«DL10�».
DL10 MEASURE VREF CIRCUIT VOLTAGE AT PFE/DPFE SENSOR
l Key off.
l Disconnect PFE/DPFE sensor.
l Key on, engine off.
l Measure voltage between VREF circuit and SIG RTN circuit at PFE/DPFE sensor vehicle harness connector.
l Is voltage between 4.0 and 6.0 volts?
Yes
REPLACE PFE/DPFE sensor. RERUN �«Quick Test�».
No
RECONNECT PFE/DPFE sensor. GO to Pinpoint Test Step �«C1�».
In a nutshell:
The 335 code is most likely the DPFE sensor.
The 172 code is most likely an O2 sensor.
The 522 code may have been due to the A/C being switched on during KOER test or if an auto not being in Park or if a manual, having the clutch pedal pushed in.
FWIW, you learned the hard way that EGR valves seldom go bad.
Stalling at idle is usually a vacuum leak or an IAC issue.
Good luck and stay away from that shop.
Steve
98 Contour SE Sport 2.5 Duratec ATX The wifey's car
89 Taurus SHO - 246K miles
94 SHO ATX - 190K
1997 F-150 5.4L ATX - The Workhorse 150K.
ANY THREAD WITH "OMG" or "WTF" ETC IN THE TITLE WILL BE IGNORED!
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