Code P1400,& P0340

[danny37363]

cAN ANYONE PLEASE TELL ME WHAT THESE CODES MEAN?

What should I do to correct this problem? It is a 1996 Ford Tarus.

Thanks,

Danny

[shorod]

The code P1400 is a Ford Enhanced OBD-II code for "Differential Pressure Feedback Electronic Sensor circuit Low Voltage." There are a lot of posts on this forum related to faulty DPFE sensor failures. Do a quick search for DPFE. Most suggest getting a factory Ford replacement sensor.

The P0340 is a generic OBD-II code for Camshaft Position (CMP) Sensor malfunction/no signal. If this is a legitimate code, your car probably won't start or stay running well at all.

-Rod

[TomV]

Originally Posted by shorod

The code P1400 is a Ford Enhanced OBD-II code for "Differential Pressure Feedback Electronic Sensor circuit Low Voltage." There are a lot of posts on this forum related to faulty DPFE sensor failures. Do a quick search for DPFE. Most suggest getting a factory Ford replacement sensor.

The P0340 is a generic OBD-II code for Camshaft Position (CMP) Sensor malfunction/no signal. If this is a legitimate code, your car probably won't start or stay running well at all.

-Rod

In my experience with the CMP code (1997) I had absolutely no symptoms of malfunction except for the engine light. The magnet was broken off the sensor and it damaged the synchronizer vane. Once the components were replaced, I noticed no improvement in performance or gas mileage. The only reason I replaced them was to pass my state-mandated emissions test.

I do not understand why the car performed fine with the faulty components. It seems odd that the $200 of parts would be on the car unless they were really needed. Perhaps not all cars need the parts, but some do and this ensures that they all work the same.

[shorod]

Originally Posted by TomV

In my experience with the CMP code (1997) I had absolutely no symptoms of malfunction except for the engine light. The magnet was broken off the sensor and it damaged the synchronizer vane. Once the components were replaced, I noticed no improvement in performance or gas mileage. The only reason I replaced them was to pass my state-mandated emissions test.

I do not understand why the car performed fine with the faulty components. It seems odd that the $200 of parts would be on the car unless they were really needed. Perhaps not all cars need the parts, but some do and this ensures that they all work the same.

Interesting. Maybe on your car they only used the CMP to determine what cylinder is missing in the event the knock sensor detects a misfire. If you didn't have a misfire, the PCM wasn't using the signal for any calculations, but did detect that the signal was out of range.

If I think about it in the next day or two, I'll have to pull the "Description and Operation" section up for my 1998 Taurus SHO and see what it says. I can compare that against the regular 1998 Taurus.

-Rod

[shorod]

According to my service manual, the CMP sensor provides camshaft position information which is used by the powertrain control module (PCM) (12A650) for fuel synchronization.

-Rod