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P0401 Fault in 1995 Ford Crown Victoria - Stalls After Start, DPFE Sensor Suspected?

Model: 95 Crown Vic Fault Code: P0401 Posted: 2016-07-13 17:36

Hi everyone, I'm experiencing a P0401 diagnostic code on my 1995 Ford Crown Victoria. The car starts fine immediately but stalls within one second of ignition. If I hold the throttle open for about one minute during startup, it runs smoothly and stays running throughout the drive. A few months ago, we replaced the EGR valve, EGR solenoid, and IAC (Idle Air Control) valve. Despite these repairs, the issue persists. Based on online research, I'm now wondering if the Differential Pressure Feedback Sensor (DPFE) might be faulty — could this be the root cause? Any insights or testing suggestions would be greatly appreciated.

Related fault codes
P0401
Comments (8)
Anonymous 2016-07-14 10:39

The DPFE sensor is often the culprit for P0401. I recommend testing its signal voltage before replacing it — this can save money and avoid unnecessary parts replacement. You might find helpful tutorials on YouTube, especially with pictures showing the sensor location. It's located at the rear of the engine, slightly to the left of the center of the intake manifold. Older models have a round sensor; newer ones are rectangular. Viewed from the front or passenger side, it’s easier to spot.

Anonymous 2016-07-14 21:16

I’ll grab one from a junkyard and test it — $2 should be enough to confirm if it's the issue.

Anonymous 2016-07-19 19:18

A clogged EGR intake passage could also cause this symptom. Make sure the passages are fully clean and unobstructed.

Anonymous 2016-07-19 19:32

I cleaned both the EGR and IAC, and they were clear — no issues found during that process.

Anonymous 2016-07-19 19:59

What exactly did you clean and replace in your previous maintenance?

Anonymous 2016-07-19 20:06

Please refer back to the original post for details on the repairs completed months ago.

Anonymous 2016-07-19 21:24

It's not the IAC passages — it’s more likely the EGR intake passages that may be blocked. Have you tested the DPFE sensor signal voltage?

Anonymous 2016-07-19 21:41

The EGR passages and IAC were cleaned thoroughly, and both appear clear. We haven’t yet tested the DPFE sensor signal voltage.